Deduplicating compositing scrollingCoordinator helper

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

Index: third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
diff --git a/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp b/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
index 961486217260411a00f2e2e69167b480cd775b2f..3700ada5e37ffabfadfb08398aaa633a8321b770 100644
--- a/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
+++ b/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
@@ -162,7 +162,8 @@ static inline bool isAcceleratedContents(LayoutObject& layoutObject) {
 
 // Get the scrolling coordinator in a way that works inside
 // CompositedLayerMapping's destructor.
-static ScrollingCoordinator* scrollingCoordinatorFromLayer(PaintLayer& layer) {

[Xianzhu, 2017/04/07 19:26:19]

It seems better to be PaintLayer::getScrollingCoordinator().

Then we can also use it at
https://cs.chromium.org/chromium/src/third_party/WebKit/Source/core/paint/Pai....

[Daniel Bratell, 2017/04/08 08:08:24]

Done.

Note that the null checks were not identical at the different places so it did
not replace all the code in the PaintLayer destructor. But then, the destructor
is a special place.

+ScrollingCoordinator* CompositedLayerMapping::scrollingCoordinatorFromLayer(
+    PaintLayer& layer) {
   Page* page = layer.layoutObject().frame()->page();
   return (!page) ? nullptr : page->scrollingCoordinator();
 }