Bug 261037. Support scrolled fieldsets. r=mats

--HG--
extra : rebase_source : 248521189921b2a46f0805582a3789b27c26ecbd

content/base/src/Element.cpp

@@ -502,8 +502,8 @@ Element::GetScrollFrame(nsIFrame **aStyledFrame, bool aFlushLayout)
 
   // menu frames implement GetScrollTargetFrame but we don't want
   // to use it here.  Similar for comboboxes.
-  if (frame->GetType() != nsGkAtoms::menuFrame &&
-      frame->GetType() != nsGkAtoms::comboboxControlFrame) {
+  nsIAtom* type = frame->GetType();
+  if (type != nsGkAtoms::menuFrame && type != nsGkAtoms::comboboxControlFrame) {
     nsIScrollableFrame *scrollFrame = frame->GetScrollTargetFrame();
     if (scrollFrame)
       return scrollFrame;

layout/base/nsCSSFrameConstructor.cpp

@@ -3050,39 +3050,50 @@ nsCSSFrameConstructor::ConstructFieldSetFrame(nsFrameConstructorState& aState,
   nsIContent* const content = aItem.mContent;
   nsStyleContext* const styleContext = aItem.mStyleContext;
 
-  nsIFrame* newFrame = NS_NewFieldSetFrame(mPresShell, styleContext);
+  nsIFrame* fieldsetFrame = NS_NewFieldSetFrame(mPresShell, styleContext);
 
   // Initialize it
   InitAndRestoreFrame(aState, content,
                       aState.GetGeometricParent(aStyleDisplay, aParentFrame),
-                      newFrame);
+                      fieldsetFrame);
 
   // Resolve style and initialize the frame
   nsRefPtr<nsStyleContext> fieldsetContentStyle;
   fieldsetContentStyle = mPresShell->StyleSet()->
     ResolveAnonymousBoxStyle(nsCSSAnonBoxes::fieldsetContent, styleContext);
 
+  const nsStyleDisplay* fieldsetContentDisplay = fieldsetContentStyle->StyleDisplay();
+  bool isScrollable = fieldsetContentDisplay->IsScrollableOverflow();
+  nsIFrame* scrollFrame = nullptr;
+  if (isScrollable) {
+    fieldsetContentStyle =
+      BeginBuildingScrollFrame(aState, content, fieldsetContentStyle,
+                               fieldsetFrame, nsCSSAnonBoxes::scrolledContent,
+                               false, scrollFrame);
+  }
+
   nsIFrame* blockFrame = NS_NewBlockFrame(mPresShell, fieldsetContentStyle,
                                           NS_BLOCK_FLOAT_MGR |
                                           NS_BLOCK_MARGIN_ROOT);
-  InitAndRestoreFrame(aState, content, newFrame, blockFrame);
+  InitAndRestoreFrame(aState, content,
+    scrollFrame ? scrollFrame : fieldsetFrame, blockFrame);
 
-  aState.AddChild(newFrame, aFrameItems, content, styleContext, aParentFrame);
+  aState.AddChild(fieldsetFrame, aFrameItems, content, styleContext, aParentFrame);
   
   // Process children
   nsFrameConstructorSaveState absoluteSaveState;
   nsFrameItems                childItems;
 
-  newFrame->AddStateBits(NS_FRAME_CAN_HAVE_ABSPOS_CHILDREN);
-  if (newFrame->IsPositioned()) {
-    aState.PushAbsoluteContainingBlock(newFrame, newFrame, absoluteSaveState);
+  blockFrame->AddStateBits(NS_FRAME_CAN_HAVE_ABSPOS_CHILDREN);
+  if (fieldsetFrame->IsPositioned()) {
+    aState.PushAbsoluteContainingBlock(blockFrame, fieldsetFrame, absoluteSaveState);
   }
 
   ProcessChildren(aState, content, styleContext, blockFrame, true,
                   childItems, true, aItem.mPendingBinding);
 
   nsFrameItems fieldsetKids;
-  fieldsetKids.AddChild(blockFrame);
+  fieldsetKids.AddChild(scrollFrame ? scrollFrame : blockFrame);
 
   for (nsFrameList::Enumerator e(childItems); !e.AtEnd(); e.Next()) {
     nsIFrame* child = e.get();
@@ -3094,21 +3105,25 @@ nsCSSFrameConstructor::ConstructFieldSetFrame(nsFrameConstructorState& aState,
       // GetAdjustedParentFrame() below depends on this frame order.
       childItems.RemoveFrame(child);
       // Make sure to reparent the legend so it has the fieldset as the parent.
-      fieldsetKids.InsertFrame(newFrame, nullptr, child);
+      fieldsetKids.InsertFrame(fieldsetFrame, nullptr, child);
       break;
     }
   }
 
+  if (isScrollable) {
+    FinishBuildingScrollFrame(scrollFrame, blockFrame);
+  }
+
   // Set the inner frame's initial child lists
   blockFrame->SetInitialChildList(kPrincipalList, childItems);
 
   // Set the outer frame's initial child list
-  newFrame->SetInitialChildList(kPrincipalList, fieldsetKids);
+  fieldsetFrame->SetInitialChildList(kPrincipalList, fieldsetKids);
 
-  newFrame->AddStateBits(NS_FRAME_MAY_HAVE_GENERATED_CONTENT);
+  fieldsetFrame->AddStateBits(NS_FRAME_MAY_HAVE_GENERATED_CONTENT);
 
   // Our new frame returned is the outer frame, which is the fieldset frame.
-  return newFrame; 
+  return fieldsetFrame; 
 }
 
 static nsIFrame*
@@ -3262,6 +3277,17 @@ nsCSSFrameConstructor::FindDataByTag(nsIAtom* aTag,
 #define COMPLEX_TAG_CREATE(_tag, _func)             \
   { &nsGkAtoms::_tag, FULL_CTOR_FCDATA(0, _func) }
 
+static bool
+IsFrameForFieldSet(nsIFrame* aFrame, nsIAtom* aFrameType)
+{
+  nsIAtom* pseudo = aFrame->StyleContext()->GetPseudo();
+  if (pseudo == nsCSSAnonBoxes::fieldsetContent ||
+      pseudo == nsCSSAnonBoxes::scrolledContent) {
+    return IsFrameForFieldSet(aFrame->GetParent(), aFrame->GetParent()->GetType());
+  }
+  return aFrameType == nsGkAtoms::fieldSetFrame;
+}
+
 /* static */
 const nsCSSFrameConstructor::FrameConstructionData*
 nsCSSFrameConstructor::FindHTMLData(Element* aElement,
@@ -3284,9 +3310,7 @@ nsCSSFrameConstructor::FindHTMLData(Element* aElement,
                "Unexpected parent for fieldset content anon box");
   if (aTag == nsGkAtoms::legend &&
       (!aParentFrame ||
-       (aParentFrame->GetType() != nsGkAtoms::fieldSetFrame &&
-        aParentFrame->StyleContext()->GetPseudo() !=
-          nsCSSAnonBoxes::fieldsetContent) ||
+       !IsFrameForFieldSet(aParentFrame, aParentFrame->GetType()) ||
        !aElement->GetParent() ||
        !aElement->GetParent()->IsHTML(nsGkAtoms::fieldset) ||
        aStyleContext->StyleDisplay()->IsFloatingStyle() ||
@@ -5919,13 +5943,8 @@ nsCSSFrameConstructor::IsValidSibling(nsIFrame*              aSibling,
 {
   nsIFrame* parentFrame = aSibling->GetParent();
   nsIAtom* parentType = nullptr;
-  nsIAtom* grandparentType = nullptr;
   if (parentFrame) {
     parentType = parentFrame->GetType();
-    nsIFrame* grandparentFrame = parentFrame->GetParent();
-    if (grandparentFrame) {
-      grandparentType = grandparentFrame->GetType();
-    }
   }
 
   uint8_t siblingDisplay = aSibling->GetDisplay();
@@ -5984,9 +6003,7 @@ nsCSSFrameConstructor::IsValidSibling(nsIFrame*              aSibling,
 
     return true;
   }
-  else if (nsGkAtoms::fieldSetFrame == parentType ||
-           (nsGkAtoms::fieldSetFrame == grandparentType &&
-            nsGkAtoms::blockFrame == parentType)) {
+  else if (IsFrameForFieldSet(parentFrame, parentType)) {
     // Legends can be sibling of legends but not of other content in the fieldset
     nsIAtom* sibType = aSibling->GetContentInsertionFrame()->GetType();
     bool legendContent = aContent->IsHTML(nsGkAtoms::legend);
@@ -7083,7 +7100,7 @@ nsCSSFrameConstructor::ContentRangeInserted(nsIContent*            aContainer,
   // fieldsets have multiple insertion points.
   NS_ASSERTION(isSingleInsert || frameType != nsGkAtoms::fieldSetFrame,
                "Unexpected parent");
-  if (frameType == nsGkAtoms::fieldSetFrame &&
+  if (IsFrameForFieldSet(parentFrame, frameType) &&
       aStartChild->Tag() == nsGkAtoms::legend) {
     // Just reframe the parent, since figuring out whether this
     // should be the new legend and then handling it is too complex.

layout/base/nsLayoutUtils.cpp

@@ -2825,7 +2825,8 @@ static int32_t gNoiseIndent = 0;
 /* static */ nscoord
 nsLayoutUtils::IntrinsicForContainer(nsRenderingContext *aRenderingContext,
                                      nsIFrame *aFrame,
-                                     IntrinsicWidthType aType)
+                                     IntrinsicWidthType aType,
+                                     uint32_t aFlags)
 {
   NS_PRECONDITION(aFrame, "null frame");
   NS_PRECONDITION(aType == MIN_WIDTH || aType == PREF_WIDTH, "bad type");
@@ -2919,15 +2920,17 @@ nsLayoutUtils::IntrinsicForContainer(nsRenderingContext *aRenderingContext,
           // fall through
         }
         case NS_STYLE_BOX_SIZING_PADDING: {
-          const nsStylePadding* stylePadding = aFrame->StylePadding();
-          nscoord pad;
-          if (GetAbsoluteCoord(stylePadding->mPadding.GetTop(), pad) ||
-              GetPercentHeight(stylePadding->mPadding.GetTop(), aFrame, pad)) {
-            heightTakenByBoxSizing += pad;
-          }
-          if (GetAbsoluteCoord(stylePadding->mPadding.GetBottom(), pad) ||
-              GetPercentHeight(stylePadding->mPadding.GetBottom(), aFrame, pad)) {
-            heightTakenByBoxSizing += pad;
+          if (!(aFlags & IGNORE_PADDING)) {
+            const nsStylePadding* stylePadding = aFrame->StylePadding();
+            nscoord pad;
+            if (GetAbsoluteCoord(stylePadding->mPadding.GetTop(), pad) ||
+                GetPercentHeight(stylePadding->mPadding.GetTop(), aFrame, pad)) {
+              heightTakenByBoxSizing += pad;
+            }
+            if (GetAbsoluteCoord(stylePadding->mPadding.GetBottom(), pad) ||
+                GetPercentHeight(stylePadding->mPadding.GetBottom(), aFrame, pad)) {
+              heightTakenByBoxSizing += pad;
+            }
           }
           // fall through
         }
@@ -2978,18 +2981,22 @@ nsLayoutUtils::IntrinsicForContainer(nsRenderingContext *aRenderingContext,
   // percentages do not operate linearly.
   // Doing this is ok because although percentages aren't handled
   // linearly, they are handled monotonically.
-  nscoord coordOutsideWidth = offsets.hPadding;
-  float pctOutsideWidth = offsets.hPctPadding;
-
+  nscoord coordOutsideWidth = 0;
+  float pctOutsideWidth = 0;
   float pctTotal = 0.0f;
 
-  if (boxSizing == NS_STYLE_BOX_SIZING_PADDING) {
-    min += coordOutsideWidth;
-    result = NSCoordSaturatingAdd(result, coordOutsideWidth);
-    pctTotal += pctOutsideWidth;
+  if (!(aFlags & IGNORE_PADDING)) {
+    coordOutsideWidth += offsets.hPadding;
+    pctOutsideWidth += offsets.hPctPadding;
 
-    coordOutsideWidth = 0;
-    pctOutsideWidth = 0.0f;
+    if (boxSizing == NS_STYLE_BOX_SIZING_PADDING) {
+      min += coordOutsideWidth;
+      result = NSCoordSaturatingAdd(result, coordOutsideWidth);
+      pctTotal += pctOutsideWidth;
+
+      coordOutsideWidth = 0;
+      pctOutsideWidth = 0.0f;
+    }
   }
 
   coordOutsideWidth += offsets.hBorder;

layout/base/nsLayoutUtils.h

@@ -988,9 +988,13 @@ public:
    * and margin.
    */
   enum IntrinsicWidthType { MIN_WIDTH, PREF_WIDTH };
+  enum {
+    IGNORE_PADDING = 0x01
+  };
   static nscoord IntrinsicForContainer(nsRenderingContext* aRenderingContext,
                                        nsIFrame* aFrame,
-                                       IntrinsicWidthType aType);
+                                       IntrinsicWidthType aType,
+                                       uint32_t aFlags = 0);
 
   /*
    * Convert nsStyleCoord to nscoord when percentages depend on the

layout/forms/nsFieldSetFrame.cpp

@@ -15,6 +15,7 @@
 #include "nsStyleConsts.h"
 #include "nsDisplayList.h"
 #include "nsRenderingContext.h"
+#include "nsIScrollableFrame.h"
 #include "mozilla/Likely.h"
 
 using namespace mozilla;
@@ -78,6 +79,10 @@ public:
     return nsContainerFrame::IsFrameOfType(aFlags &
              ~nsIFrame::eCanContainOverflowContainers);
   }
+  virtual nsIScrollableFrame* GetScrollTargetFrame() MOZ_OVERRIDE
+  {
+    return do_QueryFrame(GetInner());
+  }
 
 #ifdef ACCESSIBILITY  
   virtual mozilla::a11y::AccType AccessibleType() MOZ_OVERRIDE;
@@ -356,10 +361,14 @@ nsFieldSetFrame::GetIntrinsicWidth(nsRenderingContext* aRenderingContext,
   }
 
   if (nsIFrame* inner = GetInner()) {
+    // Ignore padding on the inner, since the padding will be applied to the
+    // outer instead, and the padding computed for the inner is wrong
+    // for percentage padding.
     contentWidth =
-      nsLayoutUtils::IntrinsicForContainer(aRenderingContext, inner, aType);
+      nsLayoutUtils::IntrinsicForContainer(aRenderingContext, inner, aType,
+                                           nsLayoutUtils::IGNORE_PADDING);
   }
-      
+
   return std::max(legendWidth, contentWidth);
 }
 
@@ -444,7 +453,10 @@ nsFieldSetFrame::Reflow(nsPresContext*           aPresContext,
 
   // We don't allow fieldsets to break vertically. If we did, we'd
   // need logic here to push and pull overflow frames.
-  nsSize availSize(aReflowState.ComputedWidth(), NS_UNCONSTRAINEDSIZE);
+  // Since we're not applying our padding in this frame, we need to add it here
+  // to compute the available width for our children.
+  nsSize availSize(aReflowState.ComputedWidth() + aReflowState.mComputedPadding.LeftRight(),
+                   NS_UNCONSTRAINEDSIZE);
   NS_ASSERTION(!inner ||
       nsLayoutUtils::IntrinsicForContainer(aReflowState.rendContext,
                                            inner,
@@ -459,8 +471,7 @@ nsFieldSetFrame::Reflow(nsPresContext*           aPresContext,
                "Bogus availSize.width; should be bigger");
 
   // get our border and padding
-  const nsMargin &borderPadding = aReflowState.mComputedBorderPadding;
-  nsMargin border = borderPadding - aReflowState.mComputedPadding;  
+  nsMargin border = aReflowState.mComputedBorderPadding - aReflowState.mComputedPadding;
 
   // Figure out how big the legend is if there is one. 
   // get the legend's margin
@@ -481,7 +492,7 @@ nsFieldSetFrame::Reflow(nsPresContext*           aPresContext,
     legendMargin = legend->GetUsedMargin();
     mLegendRect.width  = legendDesiredSize.width + legendMargin.left + legendMargin.right;
     mLegendRect.height = legendDesiredSize.height + legendMargin.top + legendMargin.bottom;
-    mLegendRect.x = borderPadding.left;
+    mLegendRect.x = 0;
     mLegendRect.y = 0;
 
     nscoord oldSpace = mLegendSpace;
@@ -513,16 +524,22 @@ nsFieldSetFrame::Reflow(nsPresContext*           aPresContext,
   // reflow the content frame only if needed
   if (reflowInner) {
     nsHTMLReflowState kidReflowState(aPresContext, aReflowState, inner,
-                                     availSize);
+                                     availSize, -1, -1, nsHTMLReflowState::CALLER_WILL_INIT);
+    // Override computed padding, in case it's percentage padding
+    kidReflowState.Init(aPresContext, -1, -1, nullptr,
+                        &aReflowState.mComputedPadding);
     // Our child is "height:100%" but we actually want its height to be reduced
     // by the amount of content-height the legend is eating up, unless our
     // height is unconstrained (in which case the child's will be too).
     if (aReflowState.ComputedHeight() != NS_UNCONSTRAINEDSIZE) {
-      kidReflowState.SetComputedHeight(std::max(0, aReflowState.ComputedHeight() - mLegendSpace));
+      kidReflowState.SetComputedHeight(
+         std::max(0, aReflowState.ComputedHeight() - mLegendSpace));
     }
 
-    kidReflowState.mComputedMinHeight =
-      std::max(0, aReflowState.mComputedMinHeight - mLegendSpace);
+    if (aReflowState.mComputedMinHeight > 0) {
+      kidReflowState.mComputedMinHeight =
+        std::max(0, aReflowState.mComputedMinHeight - mLegendSpace);
+    }
 
     if (aReflowState.mComputedMaxHeight != NS_UNCONSTRAINEDSIZE) {
       kidReflowState.mComputedMaxHeight =
@@ -533,7 +550,7 @@ nsFieldSetFrame::Reflow(nsPresContext*           aPresContext,
     // Reflow the frame
     NS_ASSERTION(kidReflowState.mComputedMargin == nsMargin(0,0,0,0),
                  "Margins on anonymous fieldset child not supported!");
-    nsPoint pt(borderPadding.left, borderPadding.top + mLegendSpace);
+    nsPoint pt(border.left, border.top + mLegendSpace);
     ReflowChild(inner, aPresContext, kidDesiredSize, kidReflowState,
                 pt.x, pt.y, 0, aStatus);
 
@@ -542,37 +559,45 @@ nsFieldSetFrame::Reflow(nsPresContext*           aPresContext,
     NS_FRAME_TRACE_REFLOW_OUT("FieldSet::Reflow", aStatus);
   }
 
-  nsRect contentRect(0,0,0,0);
+  nsRect contentRect;
   if (inner) {
-    // We don't support margins on inner, so our "content rect" is just
-    // its rect.
+    // We don't support margins on inner, so our content rect is just the
+    // inner's border-box.
     contentRect = inner->GetRect();
   }
 
-  // use the computed width if the inner content does not fill it
-  if (aReflowState.ComputedWidth() > contentRect.width) {
-    contentRect.width = aReflowState.ComputedWidth();
+  // Our content rect must fill up the available width
+  if (availSize.width > contentRect.width) {
+    contentRect.width = availSize.width;
   }
 
   if (legend) {
-    // if the content rect is larger then the  legend we can align the legend
-    if (contentRect.width > mLegendRect.width) {
+    // the legend is postioned horizontally within the inner's content rect
+    // (so that padding on the fieldset affects the legend position).
+    nsRect innerContentRect = contentRect;
+    innerContentRect.Deflate(aReflowState.mComputedPadding);
+    // if the inner content rect is larger than the legend, we can align the legend
+    if (innerContentRect.width > mLegendRect.width) {
       int32_t align = static_cast<nsLegendFrame*>
         (legend->GetContentInsertionFrame())->GetAlign();
 
-      switch(align) {
+      switch (align) {
         case NS_STYLE_TEXT_ALIGN_RIGHT:
-          mLegendRect.x = contentRect.width - mLegendRect.width + borderPadding.left;
+          mLegendRect.x = innerContentRect.XMost() - mLegendRect.width;
           break;
         case NS_STYLE_TEXT_ALIGN_CENTER:
           // Note: rounding removed; there doesn't seem to be any need
-          mLegendRect.x = contentRect.width / 2 - mLegendRect.width / 2 + borderPadding.left;
+          mLegendRect.x = innerContentRect.width / 2 - mLegendRect.width / 2 + innerContentRect.x;
+          break;
+        default:
+          mLegendRect.x = innerContentRect.x;
           break;
       }
-  
     } else {
       // otherwise make place for the legend
-      contentRect.width = mLegendRect.width;
+      mLegendRect.x = innerContentRect.x;
+      innerContentRect.width = mLegendRect.width;
+      contentRect.width = mLegendRect.width + aReflowState.mComputedPadding.LeftRight();
     }
     // place the legend
     nsRect actualLegendRect(mLegendRect);
@@ -594,16 +619,16 @@ nsFieldSetFrame::Reflow(nsPresContext*           aPresContext,
   // Return our size and our result
   if (aReflowState.ComputedHeight() == NS_INTRINSICSIZE) {
     aDesiredSize.height = mLegendSpace + 
-                          borderPadding.TopBottom() +
-                          contentRect.height;
+                          border.TopBottom() +
+                          (inner ? inner->GetRect().height : 0);
   } else {
-    nscoord min = borderPadding.TopBottom() + mLegendRect.height;
+    nscoord min = border.TopBottom() + mLegendRect.height;
     aDesiredSize.height =
-      aReflowState.ComputedHeight() + borderPadding.TopBottom();
+      aReflowState.ComputedHeight() + aReflowState.mComputedBorderPadding.TopBottom();
     if (aDesiredSize.height < min)
       aDesiredSize.height = min;
   }
-  aDesiredSize.width = contentRect.width + borderPadding.LeftRight();
+  aDesiredSize.width = contentRect.width + border.LeftRight();
   aDesiredSize.SetOverflowAreasToDesiredBounds();
   if (legend)
     ConsiderChildOverflow(aDesiredSize.mOverflowAreas, legend);
@@ -681,9 +706,6 @@ nsFieldSetFrame::ReparentFrameList(const nsFrameList& aFrameList)
 nscoord
 nsFieldSetFrame::GetBaseline() const
 {
-  // We know inner is a block, so calling GetBaseline() on it will do
-  // the right thing (that being to return the baseline of the last line).
   nsIFrame* inner = GetInner();
-  NS_ASSERTION(nsLayoutUtils::GetAsBlock(inner), "Unexpected inner");
   return inner->GetPosition().y + inner->GetBaseline();
 }

layout/reftests/bugs/478811-1.html

@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html style="height: 100%">
+<html class="reftest-wait" style="height: 100%">
   <head>
     <script>
       function doIt() {
@@ -8,10 +8,12 @@
                        "position: absolute; left: 0; right: 0; top: 0; " +
                        "bottom: 0; background: green");
         document.getElementById("x").appendChild(d);
+        document.documentElement.removeAttribute("class");
       }
+      window.addEventListener("MozReftestInvalidate", doIt);
     </script>
   </head>
-  <body style="height: 100%" onload="doIt()">
+  <body style="height: 100%">
     <fieldset id="x" style="position: relative; display: table; width: 50%;
                             height: 50%; top: 25%; left: 25%">
     </fieldset>

layout/reftests/forms/fieldset/dynamic-legend-scroll-1-ref.html

@@ -0,0 +1,24 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+<style>
+fieldset { 
+  background:pink;
+  overflow:hidden;
+  height:100px;
+}
+legend::after { content:"legend"; }
+p {
+  background:lime;
+  height:20px;
+}
+</style>
+</head>
+<body>
+<fieldset id="f1"><legend></legend><p></p></fieldset>
+<br>
+<fieldset id="f2"><legend></legend><p></p></fieldset>
+<br>
+<fieldset id="f3"><legend></legend></fieldset>
+</body>
+</html>

layout/reftests/forms/fieldset/dynamic-legend-scroll-1.html

@@ -0,0 +1,33 @@
+<!DOCTYPE HTML>
+<html class="reftest-wait">
+<head>
+<style>
+fieldset { 
+  background:pink;
+  overflow:hidden;
+  height:100px;
+}
+legend::after { content:"legend"; }
+p {
+  background:lime;
+  height:20px;
+}
+</style>
+</head>
+<body>
+<fieldset id="f1"><p></p></fieldset>
+<br>
+<fieldset id="f2"><p></p></fieldset>
+<br>
+<fieldset id="f3"></fieldset>
+<script>
+function doTest() {
+  f1.appendChild(document.createElement('legend'));
+  f2.insertBefore(document.createElement('legend'), f2.firstChild);
+  f3.appendChild(document.createElement('legend'));
+  document.documentElement.removeAttribute("class");
+}
+window.addEventListener("MozReftestInvalidate", doTest);
+</script>
+</body>
+</html>

layout/reftests/forms/fieldset/fieldset-hidden-1-ref.html

@@ -0,0 +1,21 @@
+<!DOCTYPE HTML>
+<html>
+<body>
+<fieldset style="width:200px; height:200px; padding:0">
+  <legend>Legend</legend>
+  <div style="overflow:hidden; height:100%;">
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+  </div>
+</fieldset>
+</body>
+</html>

layout/reftests/forms/fieldset/fieldset-hidden-1.html

@@ -0,0 +1,19 @@
+<!DOCTYPE HTML>
+<html>
+<body>
+<fieldset style="overflow:hidden; width:200px; height:200px; padding:0">
+  <legend>Legend</legend>
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+</fieldset>
+</body>
+</html>

layout/reftests/forms/fieldset/fieldset-intrinsic-width-1-ref.html

@@ -0,0 +1,8 @@
+<!DOCTYPE HTML>
+<html>
+<body>
+<fieldset style="width:0; padding:0;">
+  <div style="width:400px; height:200px;"></div>
+</fieldset>
+</body>
+</html>

layout/reftests/forms/fieldset/fieldset-intrinsic-width-1.html

@@ -0,0 +1,8 @@
+<!DOCTYPE HTML>
+<html>
+<body>
+<fieldset style="padding:50px; float:left;">
+  <div style="width:300px; height:100px;"></div>
+</fieldset>
+</body>
+</html>

layout/reftests/forms/fieldset/fieldset-overflow-auto-1-ref.html

@@ -0,0 +1,52 @@
+<!DOCTYPE HTML>
+<html><head>
+    <meta charset="utf-8">
+    <title>Testcase for bug 261037</title>
+    <style type="text/css">
+fieldset, div { 
+  background:pink;
+  overflow:auto;
+  height:100px;
+  margin:0; padding:0; border:0;
+}
+p {
+  background:blue;
+  height:100px;
+  margin:0; padding:0;
+}
+.overflow {
+  height:110px;
+}
+.abs {
+  position:absolute;
+  width:100px;
+  top:250px;
+}
+p.abs {
+  top:0;left:0;
+}
+.b { border:10px solid black; }
+.p { padding: 7px 0; }
+.p p { height:114px; }
+    </style>
+</head>
+<body>
+
+<div><p></p></div>
+<br>
+<div><p class="overflow"></p></div>
+<br>
+<div class="abs"><p class="abs"></p></div>
+<br>
+<div class="abs" style="left:120px"><p class="abs overflow"></p></div>
+<br>
+<div class="abs b" style="left:240px"><p class="abs"></p></div>
+<br>
+<div class="abs b" style="left:370px"><p class="abs overflow"></p></div>
+<br>
+<div class="abs b p" style="left:510px"><p class="abs"></p></div>
+<br>
+<div class="abs b p" style="left:640px"><p class="abs overflow"></p></div>
+
+</body>
+</html>

layout/reftests/forms/fieldset/fieldset-overflow-auto-1.html

@@ -0,0 +1,52 @@
+<!DOCTYPE HTML>
+<html><head>
+    <meta charset="utf-8">
+    <title>Testcase for bug 261037</title>
+    <style type="text/css">
+fieldset, div { 
+  background:pink;
+  overflow:auto;
+  height:100px;
+  margin:0; padding:0; border:0;
+}
+p {
+  background:blue;
+  height:100px;
+  margin:0; padding:0;
+}
+.overflow {
+  height:110px;
+}
+.abs {
+  position:absolute;
+  width:100px;
+  top:250px;
+}
+p.abs {
+  top:0;left:0;
+}
+.b { border:10px solid black; }
+.p { padding: 7px 0; }
+.p p { height:114px; }
+    </style>
+</head>
+<body>
+
+<fieldset><p></p></fieldset>
+<br>
+<fieldset><p class="overflow"></p></fieldset>
+<br>
+<fieldset class="abs"><p class="abs"></p></fieldset>
+<br>
+<fieldset class="abs" style="left:120px"><p class="abs overflow"></p></fieldset>
+<br>
+<fieldset class="abs b" style="left:240px"><p class="abs"></p></fieldset>
+<br>
+<fieldset class="abs b" style="left:370px"><p class="abs overflow"></p></fieldset>
+<br>
+<fieldset class="abs b p" style="left:510px"><p class="abs"></p></fieldset>
+<br>
+<fieldset class="abs b p" style="left:640px"><p class="abs overflow"></p></fieldset>
+
+</body>
+</html>

layout/reftests/forms/fieldset/fieldset-percentage-padding-1-ref.html

@@ -0,0 +1,19 @@
+<!DOCTYPE HTML>
+<html>
+<body>
+<div style="width:700px; border:2px solid green; overflow:hidden">
+  <fieldset style="padding:140px; width:400px;">
+    <legend>Legend</legend>
+    TextTextTextTextTextText
+  </fieldset>
+  <fieldset style="padding:140px; display:inline;">
+    <legend>Legend</legend>
+    TextTextTextTextTextText
+  </fieldset>
+  <fieldset style="padding:140px; float:left;">
+    <legend>Legend</legend>
+    TextTextTextTextTextText
+  </fieldset>
+</div>
+</body>
+</html>

layout/reftests/forms/fieldset/fieldset-percentage-padding-1.html

@@ -0,0 +1,19 @@
+<!DOCTYPE HTML>
+<html>
+<body>
+<div style="width:700px; border:2px solid green; overflow:hidden">
+  <fieldset style="padding:20%; width:400px;">
+    <legend>Legend</legend>
+    TextTextTextTextTextText
+  </fieldset>
+  <fieldset style="padding:20%; display:inline;">
+    <legend>Legend</legend>
+    TextTextTextTextTextText
+  </fieldset>
+  <fieldset style="padding:20%; float:left;">
+    <legend>Legend</legend>
+    TextTextTextTextTextText
+  </fieldset>
+</div>
+</body>
+</html>

layout/reftests/forms/fieldset/fieldset-scroll-1-ref.html

@@ -0,0 +1,9 @@
+<!DOCTYPE HTML>
+<html>
+<body>
+<fieldset style="width:200px; height:200px; padding:0">
+  <legend>Legend</legend>
+  <div style="overflow:scroll; height:100%">
+</fieldset>
+</body>
+</html>

layout/reftests/forms/fieldset/fieldset-scroll-1.html

@@ -0,0 +1,8 @@
+<!DOCTYPE HTML>
+<html>
+<body>
+<fieldset style="overflow:scroll; width:200px; height:200px; padding:0">
+  <legend>Legend</legend>
+</fieldset>
+</body>
+</html>

layout/reftests/forms/fieldset/fieldset-scrolled-1-ref.html

@@ -0,0 +1,24 @@
+<!DOCTYPE HTML>
+<html>
+<body>
+<fieldset style="width:200px; height:200px; padding:0">
+  <legend style="overflow:hidden">Legend</legend>
+  <div id="d" style="overflow:hidden; height:100%;">
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+    <p>Hello Kitty
+  </div>
+</fieldset>
+<script>
+d.scrollTop = 20;
+</script>
+</body>
+</html>

layout/reftests/forms/fieldset/fieldset-scrolled-1.html

@@ -0,0 +1,27 @@
+<!DOCTYPE HTML>
+<html class="reftest-wait">
+<body>
+<fieldset id="f" style="overflow:hidden; width:200px; height:200px; padding:0">
+  <legend style="overflow:hidden">Legend</legend>
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+  <p>Hello Kitty
+</fieldset>
+<script>
+f.scrollTop = 0;
+function doTest() {
+  f.scrollTop = 20;
+  document.documentElement.removeAttribute("class");
+}
+window.addEventListener("MozReftestInvalidate", doTest);
+</script>
+</body>
+</html>

layout/reftests/forms/fieldset/positioned-container-1-ref.html

@@ -0,0 +1,11 @@
+<!DOCTYPE HTML>
+<html>
+<body>
+<fieldset style="position:relative; overflow:hidden; width:500px; height:500px;">
+  <legend>Legend</legend>
+  <div style="height:1000px;">
+    <div style="position:absolute; left:20px; top:20px; background:yellow;">Abs-pos</div>
+  </div>
+</fieldset>
+</body>
+</html>

layout/reftests/forms/fieldset/positioned-container-1.html

@@ -0,0 +1,14 @@
+<!DOCTYPE HTML>
+<html>
+<body>
+<fieldset id="f" style="position:relative; overflow:hidden; width:500px; height:500px;">
+  <legend>Legend</legend>
+  <div style="height:1000px;">
+    <div style="position:absolute; left:20px; top:50px; background:yellow;">Abs-pos</div>
+  </div>
+</fieldset>
+<script>
+f.scrollTop = 30;
+</script>
+</body>
+</html>

layout/reftests/forms/fieldset/reftest.list

@@ -0,0 +1,8 @@
+== dynamic-legend-scroll-1.html dynamic-legend-scroll-1-ref.html
+== fieldset-hidden-1.html fieldset-hidden-1-ref.html
+== fieldset-intrinsic-width-1.html fieldset-intrinsic-width-1-ref.html
+== fieldset-percentage-padding-1.html fieldset-percentage-padding-1-ref.html
+== fieldset-scroll-1.html fieldset-scroll-1-ref.html
+== fieldset-scrolled-1.html fieldset-scrolled-1-ref.html
+== fieldset-overflow-auto-1.html fieldset-overflow-auto-1-ref.html
+== positioned-container-1.html positioned-container-1-ref.html

layout/reftests/forms/reftest.list

@@ -6,6 +6,9 @@ include button/reftest.list
 # legend element
 include legend/reftest.list
 
+# fieldset element
+include fieldset/reftest.list
+
 # placeholder
 include placeholder/reftest.list
 

layout/style/forms.css

@@ -14,6 +14,9 @@
   display: block;
   unicode-bidi: inherit;
   text-overflow: inherit;
+  overflow: inherit;
+  padding: inherit;
+  position: inherit;
   height: 100%;   /* Need this so percentage heights of kids work right */
 }