Page::chrome() should return a reference.

Source/core/rendering/RenderLayerCompositor.cpp

Index: Source/core/rendering/RenderLayerCompositor.cpp
diff --git a/Source/core/rendering/RenderLayerCompositor.cpp b/Source/core/rendering/RenderLayerCompositor.cpp
index 2421fe406af9e1d86279739831e01b81e549e73e..4b2c4d051671c05c0ec5db745f3f36cc37cec263 100644
--- a/Source/core/rendering/RenderLayerCompositor.cpp
+++ b/Source/core/rendering/RenderLayerCompositor.cpp
@@ -262,7 +262,7 @@ void RenderLayerCompositor::cacheAcceleratedCompositingFlags()
         // on a chrome that doesn't allow accelerated compositing.
         if (hasAcceleratedCompositing) {
             if (Page* page = this->page()) {
-                ChromeClient* chromeClient = page->chrome()->client();
+                ChromeClient* chromeClient = page->chrome().client();
                 m_compositingTriggers = chromeClient->allowedCompositingTriggers();
                 hasAcceleratedCompositing = m_compositingTriggers;
             }
@@ -321,7 +321,7 @@ void RenderLayerCompositor::didChangeVisibleRect()
     IntRect visibleRect = m_clipLayer ? IntRect(IntPoint(), frameView->contentsSize()) : frameView->visibleContentRect();
     if (rootLayer->visibleRectChangeRequiresFlush(visibleRect)) {
         if (Page* page = this->page())
-            page->chrome()->client()->scheduleCompositingLayerFlush();
+            page->chrome().client()->scheduleCompositingLayerFlush();
     }
 }
 
@@ -2471,7 +2471,7 @@ void RenderLayerCompositor::attachRootLayer(RootLayerAttachment attachment)
             if (!page)
                 return;
 
-            page->chrome()->client()->attachRootGraphicsLayer(frame, rootGraphicsLayer());
+            page->chrome().client()->attachRootGraphicsLayer(frame, rootGraphicsLayer());
             break;
         }
         case RootLayerAttachedViaEnclosingFrame: {
@@ -2510,7 +2510,7 @@ void RenderLayerCompositor::detachRootLayer()
         if (!page)
             return;
 
-        page->chrome()->client()->attachRootGraphicsLayer(frame, 0);
+        page->chrome().client()->attachRootGraphicsLayer(frame, 0);
     }
     break;
     case RootLayerUnattached:
@@ -2714,7 +2714,7 @@ ScrollingCoordinator* RenderLayerCompositor::scrollingCoordinator() const
 GraphicsLayerFactory* RenderLayerCompositor::graphicsLayerFactory() const
 {
     if (Page* page = this->page())
-        return page->chrome()->client()->graphicsLayerFactory();
+        return page->chrome().client()->graphicsLayerFactory();
 
     return 0;
 }