Backed out changeset 45a57448087d (bug 1364295) for failing mochitest gfx/layers/apz/test/mochitest/test_bug982141.html on Android 4.3 API 16. r=backout

layout/base/nsLayoutUtils.cpp

@@ -39,7 +39,6 @@
 #include "nsViewManager.h"
 #include "nsPlaceholderFrame.h"
 #include "nsIScrollableFrame.h"
-#include "nsSubDocumentFrame.h"
 #include "nsIDOMEvent.h"
 #include "nsDisplayList.h"
 #include "nsRegion.h"
@@ -3426,15 +3425,13 @@ nsLayoutUtils::CalculateAndSetDisplayPortMargins(nsIScrollableFrame* aScrollFram
       content, presShell, displayportMargins, 0, aRepaintMode);
 }
 
-bool
+void
 nsLayoutUtils::MaybeCreateDisplayPort(nsDisplayListBuilder& aBuilder,
-                                      nsIFrame* aScrollFrame,
-                                      RepaintMode aRepaintMode)
-{
+                                      nsIFrame* aScrollFrame) {
   nsIContent* content = aScrollFrame->GetContent();
   nsIScrollableFrame* scrollableFrame = do_QueryFrame(aScrollFrame);
   if (!content || !scrollableFrame) {
-    return false;
+    return;
   }
 
   bool haveDisplayPort = HasDisplayPort(content);
@@ -3450,7 +3447,7 @@ nsLayoutUtils::MaybeCreateDisplayPort(nsDisplayListBuilder& aBuilder,
 
     // If we don't already have a displayport, calculate and set one.
     if (!haveDisplayPort) {
-      CalculateAndSetDisplayPortMargins(scrollableFrame, aRepaintMode);
+      CalculateAndSetDisplayPortMargins(scrollableFrame, nsLayoutUtils::RepaintMode::DoNotRepaint);
 #ifdef DEBUG
       haveDisplayPort = HasDisplayPort(content);
       MOZ_ASSERT(haveDisplayPort, "should have a displayport after having just set it");
@@ -3459,9 +3456,7 @@ nsLayoutUtils::MaybeCreateDisplayPort(nsDisplayListBuilder& aBuilder,
 
     // Record that the we now have a scrollable display port.
     aBuilder.SetHaveScrollableDisplayPort();
-    return true;
   }
-  return false;
 }
 
 nsIScrollableFrame*
@@ -3500,43 +3495,6 @@ nsLayoutUtils::SetZeroMarginDisplayPortOnAsyncScrollableAncestors(nsIFrame* aFra
   }
 }
 
-bool
-nsLayoutUtils::MaybeCreateDisplayPortInFirstScrollFrameEncountered(
-  nsIFrame* aFrame, nsDisplayListBuilder& aBuilder)
-{
-  nsIScrollableFrame* sf = do_QueryFrame(aFrame);
-  if (sf) {
-    if (MaybeCreateDisplayPort(aBuilder, aFrame, RepaintMode::Repaint)) {
-      return true;
-    }
-  }
-  if (aFrame->IsPlaceholderFrame()) {
-    nsPlaceholderFrame* placeholder = static_cast<nsPlaceholderFrame*>(aFrame);
-    if (MaybeCreateDisplayPortInFirstScrollFrameEncountered(
-          placeholder->GetOutOfFlowFrame(), aBuilder)) {
-      return true;
-    }
-  }
-  if (aFrame->IsSubDocumentFrame()) {
-    nsIPresShell* presShell =
-      static_cast<nsSubDocumentFrame*>(aFrame)->GetSubdocumentPresShellForPainting(0);
-    nsIFrame* root = presShell ? presShell->GetRootFrame() : nullptr;
-    if (root) {
-      if (MaybeCreateDisplayPortInFirstScrollFrameEncountered(root, aBuilder)) {
-        return true;
-      }
-    }
-  }
-
-  for (nsIFrame* child : aFrame->PrincipalChildList()) {
-    if (MaybeCreateDisplayPortInFirstScrollFrameEncountered(child, aBuilder)) {
-      return true;
-    }
-  }
-
-  return false;
-}
-
 void
 nsLayoutUtils::ExpireDisplayPortOnAsyncScrollableAncestor(nsIFrame* aFrame)
 {
@@ -3727,11 +3685,6 @@ nsLayoutUtils::PaintFrame(gfxContext* aRenderingContext, nsIFrame* aFrame,
     }
   }
 
-  builder.ClearHaveScrollableDisplayPort();
-  if (builder.IsPaintingToWindow()) {
-    MaybeCreateDisplayPortInFirstScrollFrameEncountered(aFrame, builder);
-  }
-
   nsRect dirtyRect = visibleRegion.GetBounds();
 
   {

layout/base/nsLayoutUtils.h

@@ -1066,10 +1066,6 @@ public:
                                         const nscoord aRadii[8],
                                         const nsRect& aTestRect);
 
-  static bool MaybeCreateDisplayPortInFirstScrollFrameEncountered(
-    nsIFrame* aFrame, nsDisplayListBuilder& aBuilder);
-
-
   enum class PaintFrameFlags : uint32_t {
     PAINT_IN_TRANSFORM = 0x01,
     PAINT_SYNC_DECODE_IMAGES = 0x02,
@@ -2818,15 +2814,10 @@ public:
    * displayport yet (as tracked by |aBuilder|), calculate and set a
    * displayport.
    *
-   * If this is called during display list building pass DoNotRepaint in
-   * aRepaintMode.
-   *
-   * Returns true if there is a displayport on an async scrollable scrollframe
-   * after this call, either because one was just added or it already existed.
+   * This is intended to be called during display list building.
    */
-  static bool MaybeCreateDisplayPort(nsDisplayListBuilder& aBuilder,
-                                     nsIFrame* aScrollFrame,
-                                     RepaintMode aRepaintMode);
+  static void MaybeCreateDisplayPort(nsDisplayListBuilder& aBuilder,
+                                     nsIFrame* aScrollFrame);
 
   static nsIScrollableFrame* GetAsyncScrollableAncestorFrame(nsIFrame* aTarget);
 

layout/generic/nsGfxScrollFrame.cpp

@@ -3621,6 +3621,8 @@ ScrollFrameHelper::DecideScrollableLayer(nsDisplayListBuilder* aBuilder,
     wasUsingDisplayPort = nsLayoutUtils::HasDisplayPort(content);
 
     if (aAllowCreateDisplayPort) {
+      nsLayoutUtils::MaybeCreateDisplayPort(*aBuilder, mOuter);
+
       nsRect displayportBase = *aDirtyRect;
       nsPresContext* pc = mOuter->PresContext();
       if (mIsRoot && (pc->IsRootContentDocument() || !pc->GetParentPresContext())) {

layout/painting/nsDisplayList.h

@@ -586,7 +586,6 @@ public:
 
   bool HaveScrollableDisplayPort() const { return mHaveScrollableDisplayPort; }
   void SetHaveScrollableDisplayPort() { mHaveScrollableDisplayPort = true; }
-  void ClearHaveScrollableDisplayPort() { mHaveScrollableDisplayPort = false; }
 
   bool SetIsCompositingCheap(bool aCompositingCheap) {
     bool temp = mIsCompositingCheap;