Bug 653930 - Setting marginWidth and marginHeight on an iframe should trigger a reflow.r=bz

content/base/src/nsFrameLoader.cpp

@@ -862,6 +862,31 @@ nsFrameLoader::Show(PRInt32 marginWidth, PRInt32 marginHeight,
   return PR_TRUE;
 }
 
+void
+nsFrameLoader::MarginsChanged(PRUint32 aMarginWidth,
+                              PRUint32 aMarginHeight)
+{
+  // We assume that the margins are always zero for remote frames.
+  if (mRemoteFrame)
+    return;
+
+  // If there's no docshell, we're probably not up and running yet.
+  // nsFrameLoader::Show() will take care of setting the right
+  // margins.
+  if (!mDocShell)
+    return;
+
+  // Set the margins
+  mDocShell->SetMarginWidth(aMarginWidth);
+  mDocShell->SetMarginHeight(aMarginHeight);
+
+  // Trigger a restyle if there's a prescontext
+  nsRefPtr<nsPresContext> presContext;
+  mDocShell->GetPresContext(getter_AddRefs(presContext));
+  if (presContext)
+    presContext->RebuildAllStyleData(nsChangeHint(0));
+}
+
 bool
 nsFrameLoader::ShowRemoteFrame(const nsIntSize& size)
 {

content/base/src/nsFrameLoader.h

@@ -207,6 +207,11 @@ public:
               PRInt32 scrollbarPrefX, PRInt32 scrollbarPrefY,
               nsSubDocumentFrame* frame);
 
+  /**
+   * Called when the margin properties of the containing frame are changed.
+   */
+  void MarginsChanged(PRUint32 aMarginWidth, PRUint32 aMarginHeight);
+
   /**
    * Called from the layout frame associated with this frame loader, when
    * the frame is being torn down; this notifies us that out widget and view

layout/generic/nsSubDocumentFrame.cpp

@@ -700,6 +700,17 @@ nsSubDocumentFrame::AttributeChanged(PRInt32 aNameSpaceID,
         FrameNeedsReflow(rootFrame, nsIPresShell::eResize, NS_FRAME_IS_DIRTY);
     }
   }
+  else if (aAttribute == nsGkAtoms::marginwidth ||
+           aAttribute == nsGkAtoms::marginheight) {
+
+    // Retrieve the attributes
+    nsIntSize margins = GetMarginAttributes();
+
+    // Notify the frameloader
+    nsRefPtr<nsFrameLoader> frameloader = FrameLoader();
+    if (frameloader)
+      frameloader->MarginsChanged(margins.width, margins.height);
+  }
   else if (aAttribute == nsGkAtoms::type) {
     if (!mFrameLoader) 
       return NS_OK;