Generalize browser controls adjustment for arbitrary scrollers.

third_party/WebKit/Source/core/frame/FrameView.h

Index: third_party/WebKit/Source/core/frame/FrameView.h
diff --git a/third_party/WebKit/Source/core/frame/FrameView.h b/third_party/WebKit/Source/core/frame/FrameView.h
index a6869a32a7d866ba1b713b2fd9424383bfaed0a9..d837f607bd27b632f6da6285eaa817aaf3d48dd8 100644
--- a/third_party/WebKit/Source/core/frame/FrameView.h
+++ b/third_party/WebKit/Source/core/frame/FrameView.h
@@ -417,14 +417,6 @@ class CORE_EXPORT FrameView final
 
   void invalidatePaintForTickmarks();
 
-  // Since the compositor can resize the viewport due to browser controls and
-  // commit scroll offsets before a WebView::resize occurs, we need to adjust
-  // our scroll extents to prevent clamping the scroll offsets.
-  void setBrowserControlsViewportAdjustment(float);
-  IntSize browserControlsSize() const {
-    return IntSize(0, ceilf(m_browserControlsViewportAdjustment));
-  }
-
   IntSize maximumScrollOffsetInt() const override;
 
   // ScrollableArea interface
@@ -1071,8 +1063,6 @@ class CORE_EXPORT FrameView final
 
   Vector<IntRect> m_tickmarks;
 
-  float m_browserControlsViewportAdjustment;
-
   bool m_needsUpdateWidgetGeometries;
 
 #if ENABLE(ASSERT)