[blink] Perspective layer should be considered fixed-pos container layer

third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp

 /*
  * Copyright (C) 2009, 2010, 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 1575 matching lines @@
   FloatSize decoration_size = relative_compositing_bounds_size;
   decoration_outline_layer_->SetPosition(FloatPoint());
   if (decoration_size != decoration_outline_layer_->Size()) {
     decoration_outline_layer_->SetSize(decoration_size);
     decoration_outline_layer_->SetNeedsDisplay();
   }
   decoration_outline_layer_->SetOffsetFromLayoutObject(
       graphics_layer_->OffsetFromLayoutObject());
 }
 
-void CompositedLayerMapping::RegisterScrollingLayers() {
-  // Register fixed position layers and their containers with the scrolling
-  // coordinator.
-  ScrollingCoordinator* scrolling_coordinator =
-      owning_layer_.GetScrollingCoordinator();
-  if (!scrolling_coordinator)
-    return;
-
-  scrolling_coordinator->UpdateLayerPositionConstraint(&owning_layer_);
-
-  // Page scale is applied as a transform on the root layout view layer. Because
-  // the scroll layer is further up in the hierarchy, we need to avoid marking
-  // the root layout view layer as a container.
-  bool is_container =
-      owning_layer_.GetLayoutObject().CanContainFixedPositionObjects() &&
-      !owning_layer_.IsRootLayer();
-  scrolling_coordinator->SetLayerIsContainerForFixedPositionLayers(
-      graphics_layer_.get(), is_container);
-}
-
 void CompositedLayerMapping::UpdateInternalHierarchy() {
   // m_foregroundLayer has to be inserted in the correct order with child
   // layers, so it's not inserted here.
   if (ancestor_clipping_layer_)
     ancestor_clipping_layer_->RemoveAllChildren();
 
   graphics_layer_->RemoveFromParent();
 
   if (ancestor_clipping_layer_)
     ancestor_clipping_layer_->AddChild(graphics_layer_.get());
@@ skipping 854 matching lines @@
                                      topmost_layer, clip_parent,
                                      scrolling_coordinator);
     UpdateClipParentForGraphicsLayer(ancestor_clipping_layer_.get(),
                                      topmost_layer, clip_parent,
                                      scrolling_coordinator);
     UpdateClipParentForGraphicsLayer(graphics_layer_.get(), topmost_layer,
                                      clip_parent, scrolling_coordinator);
   }
 }
 
+void CompositedLayerMapping::RegisterScrollingLayers() {
+  // Register fixed position layers and their containers with the scrolling
+  // coordinator.
+  ScrollingCoordinator* scrolling_coordinator =
+      owning_layer_.GetScrollingCoordinator();
+  if (!scrolling_coordinator)
+    return;
+
+  scrolling_coordinator->UpdateLayerPositionConstraint(&owning_layer_);
+
+  // Page scale is applied as a transform on the root layout view layer. Because
+  // the scroll layer is further up in the hierarchy, we need to avoid marking
+  // the root layout view layer as a container.
+  bool is_container =
+      owning_layer_.GetLayoutObject().CanContainFixedPositionObjects() &&
+      !owning_layer_.IsRootLayer();
+  scrolling_coordinator->SetLayerIsContainerForFixedPositionLayers(
+      graphics_layer_.get(), is_container);
+  // Fixed-pos descendants inherits the space that has all CSS property applied,
+  // including perspective, overflow scroll/clip. Thus we also mark every layers
+  // below the main graphics layer so transforms implemented by them don't get
+  // skipped.
+  ApplyToGraphicsLayers(
+      this,
+      [scrolling_coordinator, is_container](GraphicsLayer* layer) {
+        scrolling_coordinator->SetLayerIsContainerForFixedPositionLayers(
+            layer, is_container);
+      },
+      kApplyToChildContainingLayers);
+}
+
 bool CompositedLayerMapping::UpdateSquashingLayers(
     bool needs_squashing_layers) {
   bool layers_changed = false;
 
   if (needs_squashing_layers) {
     if (!squashing_layer_) {
       squashing_layer_ =
           CreateGraphicsLayer(kCompositingReasonLayerForSquashingContents);
       squashing_layer_->SetDrawsContent(true);
       layers_changed = true;
@@ skipping 1101 matching lines @@
   } else if (graphics_layer == decoration_outline_layer_.get()) {
     name = "Decoration Layer";
   } else {
     NOTREACHED();
   }
 
   return name;
 }
 
 }  // namespace blink