Bug 579258. Change IsVaryingRelativeToMovingFrame to take the 'moving frame' as a direct parameter instead of getting it from the builder. r=tnikkel,a=joe

layout/base/nsDisplayList.cpp

@@ -752,11 +752,9 @@ nsDisplayBackground::IsUniform(nsDisplayListBuilder* aBuilder, nscolor* aColor)
 }
 
 PRBool
-nsDisplayBackground::IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuilder)
+nsDisplayBackground::IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuilder,
+                                                    nsIFrame* aFrame)
 {
-  NS_ASSERTION(aBuilder->IsMovingFrame(mFrame),
-              "IsVaryingRelativeToMovingFrame called on non-moving frame!");
-
   // theme background overrides any other background and is never fixed
   if (mIsThemed)
     return PR_FALSE;
@@ -771,14 +769,12 @@ nsDisplayBackground::IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuild
   if (!bg->HasFixedBackground())
     return PR_FALSE;
 
-  nsIFrame* movingFrame = aBuilder->GetRootMovingFrame();
-  // movingFrame is the frame that is going to be moved. It must be equal
-  // to mFrame or some ancestor of mFrame, see assertion above.
-  // If mFrame is in the same document as movingFrame, then mFrame
-  // will move relative to its viewport, which means this display item will
-  // change when it is moved. If they are in different documents, we do not
-  // want to return true because mFrame won't move relative to its viewport.
-  return movingFrame->PresContext() == presContext;
+  // If aFrame is mFrame or an ancestor in this document, and aFrame is
+  // not the viewport frame, then moving aFrame will move mFrame
+  // relative to the viewport, so our fixed-pos background will change.
+  return aFrame->GetParent() &&
+    (aFrame == mFrame ||
+     nsLayoutUtils::IsProperAncestorFrame(aFrame, mFrame));
 }
 
 PRBool
@@ -1102,10 +1098,8 @@ PRBool nsDisplayWrapList::IsUniform(nsDisplayListBuilder* aBuilder, nscolor* aCo
   return PR_FALSE;
 }
 
-PRBool nsDisplayWrapList::IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuilder) {
-  // The only existing consumer of IsVaryingRelativeToMovingFrame is
-  // nsLayoutUtils::ComputeRepaintRegionForCopy, which refrains from calling
-  // this on wrapped lists.
+PRBool nsDisplayWrapList::IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuilder,
+                                                         nsIFrame* aFrame) {
   NS_WARNING("nsDisplayWrapList::IsVaryingRelativeToMovingFrame called unexpectedly");
   // We could try to do something but let's conservatively just return PR_TRUE.
   return PR_TRUE;

layout/base/nsDisplayList.h

@@ -542,13 +542,13 @@ public:
   virtual PRBool IsUniform(nsDisplayListBuilder* aBuilder, nscolor* aColor) { return PR_FALSE; }
   /**
    * @return PR_FALSE if the painting performed by the item is invariant
-   * when frame aFrame is moved relative to aBuilder->GetRootMovingFrame().
+   * when the item's underlying frame is moved relative to aFrame.
    * In other words, if you render the item at locations P and P', the rendering
    * only differs by the translation.
-   * This can only be called when aBuilder->IsMovingFrame(mFrame) is true.
    * It return PR_TRUE for all wrapped lists.
    */
-  virtual PRBool IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuilder)
+  virtual PRBool IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuilder,
+                                                nsIFrame* aFrame)
   { return PR_FALSE; }
   /**
    * @return PR_TRUE if the contents of this item are rendered fixed relative
@@ -1309,7 +1309,8 @@ public:
                                    nsRegion* aVisibleRegion,
                                    nsRegion* aVisibleRegionBeforeMove);
   virtual PRBool IsOpaque(nsDisplayListBuilder* aBuilder);
-  virtual PRBool IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuilder);
+  virtual PRBool IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuilder,
+                                                nsIFrame* aFrame);
   virtual PRBool IsUniform(nsDisplayListBuilder* aBuilder, nscolor* aColor);
   virtual PRBool IsFixedAndCoveringViewport(nsDisplayListBuilder* aBuilder);
   virtual nsRect GetBounds(nsDisplayListBuilder* aBuilder);
@@ -1444,7 +1445,8 @@ public:
   virtual nsRect GetBounds(nsDisplayListBuilder* aBuilder);
   virtual PRBool IsOpaque(nsDisplayListBuilder* aBuilder);
   virtual PRBool IsUniform(nsDisplayListBuilder* aBuilder, nscolor* aColor);
-  virtual PRBool IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuilder);
+  virtual PRBool IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuilder,
+                                                nsIFrame* aFrame);
   virtual void Paint(nsDisplayListBuilder* aBuilder, nsIRenderingContext* aCtx);
   virtual PRBool ComputeVisibility(nsDisplayListBuilder* aBuilder,
                                    nsRegion* aVisibleRegion,

layout/base/nsLayoutDebugger.cpp

@@ -176,15 +176,12 @@ PrintDisplayListTo(nsDisplayListBuilder* aBuilder, const nsDisplayList& aList,
     }
     nscolor color;
     nsRect vis = i->GetVisibleRect();
-    fprintf(aOutput, "%s %p(%s) (%d,%d,%d,%d)(%d,%d,%d,%d)%s%s%s%s\n",
+    fprintf(aOutput, "%s %p(%s) (%d,%d,%d,%d)(%d,%d,%d,%d)%s%s\n",
             i->Name(), (void*)f, NS_ConvertUTF16toUTF8(fName).get(),
             rect.x, rect.y, rect.width, rect.height,
             vis.x, vis.y, vis.width, vis.height,
             i->IsOpaque(aBuilder) ? " opaque" : "",
-            i->IsUniform(aBuilder, &color) ? " uniform" : "",
-            f && aBuilder->IsMovingFrame(f) ? " moving" : "",
-            f && aBuilder->IsMovingFrame(f) && !i->GetList() &&
-              i->IsVaryingRelativeToMovingFrame(aBuilder) ? " varying" : "");
+            i->IsUniform(aBuilder, &color) ? " uniform" : "");
     nsDisplayList* list = i->GetList();
     if (list) {
       PrintDisplayListTo(aBuilder, *list, aIndent + 4, aOutput);

layout/generic/nsGfxScrollFrame.cpp

@@ -1525,17 +1525,18 @@ CanScrollWithBlitting(nsIFrame* aFrame, nsIFrame* aDisplayRoot)
 
 static void
 InvalidateFixedBackgroundFramesFromList(nsDisplayListBuilder* aBuilder,
+                                        nsIFrame* aMovingFrame,
                                         const nsDisplayList& aList)
 {
   for (nsDisplayItem* item = aList.GetBottom(); item; item = item->GetAbove()) {
     nsDisplayList* sublist = item->GetList();
     if (sublist) {
-      InvalidateFixedBackgroundFramesFromList(aBuilder, *sublist);
+      InvalidateFixedBackgroundFramesFromList(aBuilder, aMovingFrame, *sublist);
       continue;
     }
     nsIFrame* f = item->GetUnderlyingFrame();
-    if (f && aBuilder->IsMovingFrame(f) &&
-        item->IsVaryingRelativeToMovingFrame(aBuilder)) {
+    if (f &&
+        item->IsVaryingRelativeToMovingFrame(aBuilder, aMovingFrame)) {
       if (item->IsFixedAndCoveringViewport(aBuilder)) {
         // FrameLayerBuilder takes care of scrolling these
       } else {
@@ -1559,7 +1560,6 @@ InvalidateFixedBackgroundFrames(nsIFrame* aRootFrame,
   // Build the 'after' display list over the whole area of interest.
   nsDisplayListBuilder builder(aRootFrame, PR_FALSE, PR_TRUE);
   builder.EnterPresShell(aRootFrame, aUpdateRect);
-  builder.SetMovingFrame(aMovingFrame);
   nsDisplayList list;
   nsresult rv =
     aRootFrame->BuildDisplayListForStackingContext(&builder, aUpdateRect, &list);
@@ -1570,7 +1570,7 @@ InvalidateFixedBackgroundFrames(nsIFrame* aRootFrame,
   nsRegion visibleRegion(aUpdateRect);
   list.ComputeVisibility(&builder, &visibleRegion, nsnull);
 
-  InvalidateFixedBackgroundFramesFromList(&builder, list);
+  InvalidateFixedBackgroundFramesFromList(&builder, aMovingFrame, list);
   list.DeleteAll();
 }
 

layout/tables/nsTableFrame.cpp

@@ -1094,20 +1094,17 @@ nsDisplayTableItem::GetBounds(nsDisplayListBuilder* aBuilder) {
 }
 
 PRBool
-nsDisplayTableItem::IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuilder)
+nsDisplayTableItem::IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuilder,
+                                                   nsIFrame* aFrame)
 {
   if (!mPartHasFixedBackground)
     return PR_FALSE;
 
-  // aAncestorFrame is the frame that is going to be moved.
-  // Check if mFrame is equal to aAncestorFrame or aAncestorFrame is an
-  // ancestor of mFrame in the same document. If this is true, mFrame
-  // will move relative to its viewport, which means this display item will
-  // change when it is moved.  If they are in different documents, we do not
-  // want to return true because mFrame won't move relative to its viewport.
-  nsIFrame* rootMover = aBuilder->GetRootMovingFrame();
-  return mFrame == rootMover ||
-    nsLayoutUtils::IsProperAncestorFrame(rootMover, mFrame);
+  // If aFrame is mFrame or an ancestor in this document, and aFrame is
+  // not the viewport frame, then moving aFrame will move mFrame
+  // relative to the viewport, so our fixed-pos background will change.
+  return mFrame == aFrame ||
+    nsLayoutUtils::IsProperAncestorFrame(aFrame, mFrame);
 }
 
 /* static */ void

layout/tables/nsTableFrame.h

@@ -79,7 +79,8 @@ public:
   nsDisplayTableItem(nsIFrame* aFrame) : nsDisplayItem(aFrame),
       mPartHasFixedBackground(PR_FALSE) {}
 
-  virtual PRBool IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuilder);
+  virtual PRBool IsVaryingRelativeToMovingFrame(nsDisplayListBuilder* aBuilder,
+                                                nsIFrame* aFrame);
   // With collapsed borders, parts of the collapsed border can extend outside
   // the table part frames, so allow this display element to blow out to our
   // overflow rect. This is also useful for row frames that have spanning