Implement overscroll support for the virtual keyboard.

content/browser/renderer_host/render_widget_host_view_aura.h

Index: content/browser/renderer_host/render_widget_host_view_aura.h
diff --git a/content/browser/renderer_host/render_widget_host_view_aura.h b/content/browser/renderer_host/render_widget_host_view_aura.h
index 417729521c14f78efcb118cf3291d6e7dd91f279..49fbee202deade6fb04c6e49cfc9ee8a559185d6 100644
--- a/content/browser/renderer_host/render_widget_host_view_aura.h
+++ b/content/browser/renderer_host/render_widget_host_view_aura.h
@@ -40,6 +40,7 @@
 #include "ui/compositor/layer_owner_delegate.h"
 #include "ui/gfx/display_observer.h"
 #include "ui/gfx/rect.h"
+#include "ui/keyboard/keyboard_controller_observer.h"
 #include "ui/wm/public/activation_change_observer.h"
 #include "ui/wm/public/activation_delegate.h"
 
@@ -101,7 +102,8 @@ class CONTENT_EXPORT RenderWidgetHostViewAura
       public BrowserAccessibilityDelegate,
       public DelegatedFrameEvictorClient,
       public base::SupportsWeakPtr<RenderWidgetHostViewAura>,
-      public cc::DelegatedFrameResourceCollectionClient {
+      public cc::DelegatedFrameResourceCollectionClient,
+      public keyboard::KeyboardControllerObserver {
  public:
   // Displays and controls touch editing elements such as selection handles.
   class TouchEditingClient {
@@ -241,6 +243,7 @@ class CONTENT_EXPORT RenderWidgetHostViewAura
   virtual void OnSwapCompositorFrame(
       uint32 output_surface_id,
       scoped_ptr<cc::CompositorFrame> frame) OVERRIDE;
+  virtual float GetOverdrawBottomHeight() const OVERRIDE;
 #if defined(OS_WIN)
   virtual void SetParentNativeViewAccessible(
       gfx::NativeViewAccessible accessible_parent) OVERRIDE;
@@ -389,6 +392,9 @@ class CONTENT_EXPORT RenderWidgetHostViewAura
   virtual void OnLayerRecreated(ui::Layer* old_layer,
                                 ui::Layer* new_layer) OVERRIDE;
 
+  // Overridded from keyboard::KeyboardControllerObserver:
+  virtual void OnKeyboardBoundsChanging(const gfx::Rect& new_bounds) OVERRIDE;
+
  private:
   FRIEND_TEST_ALL_PREFIXES(RenderWidgetHostViewAuraTest, SetCompositionText);
   FRIEND_TEST_ALL_PREFIXES(RenderWidgetHostViewAuraTest, TouchEventState);
@@ -406,6 +412,8 @@ class CONTENT_EXPORT RenderWidgetHostViewAura
                            UpdateCursorIfOverSelf);
   FRIEND_TEST_ALL_PREFIXES(RenderWidgetHostViewAuraCopyRequestTest,
                            DestroyedAfterCopyRequest);
+  FRIEND_TEST_ALL_PREFIXES(RenderWidgetHostViewAuraKeyboardTest,
+                           OverscrollTest);
 
   class WindowObserver;
   friend class WindowObserver;
@@ -744,6 +752,9 @@ class CONTENT_EXPORT RenderWidgetHostViewAura
   // etc.
   scoped_ptr<content::LegacyRenderWidgetHostHWND>
       legacy_render_widget_host_HWND_;
+#elif defined(OS_CHROMEOS)
+  // Bounds of onscreen keyboard.
+  gfx::Rect virtual_keyboard_bounds_;
 #endif
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewAura);
 };