Fold ScrollingCoordinatorChromium into ScrollingCoordinator and devirtualize

Source/WebCore/page/Page.h

Index: Source/WebCore/page/Page.h
diff --git a/Source/WebCore/page/Page.h b/Source/WebCore/page/Page.h
index 7a262690df9d71163de4e27441885fd30f4dfb85..f682ff3fe305666f98bc981cb52c206a41fb07e4 100644
--- a/Source/WebCore/page/Page.h
+++ b/Source/WebCore/page/Page.h
@@ -198,7 +198,6 @@ public:
 
     ScrollingCoordinator* scrollingCoordinator();
 
-    String scrollingStateTreeAsText();
     String mainThreadScrollingReasonsAsText();
     PassRefPtr<ClientRectList> nonFastScrollableRects(const Frame*);
 
@@ -274,11 +273,6 @@ public:
     bool shouldSuppressScrollbarAnimations() const { return m_suppressScrollbarAnimations; }
     void setShouldSuppressScrollbarAnimations(bool suppressAnimations);
 
-    bool rubberBandsAtBottom();
-    void setRubberBandsAtBottom(bool);
-    bool rubberBandsAtTop();
-    void setRubberBandsAtTop(bool);
-
     // Page and FrameView both store a Pagination value. Page::pagination() is set only by API,
     // and FrameView::pagination() is set only by CSS. Page::pagination() will affect all
     // FrameViews in the page cache, but FrameView::pagination() only affects the current