Implement overscroll support for the virtual keyboard.

content/browser/renderer_host/render_widget_host_view_base.cc

Index: content/browser/renderer_host/render_widget_host_view_base.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_base.cc b/content/browser/renderer_host/render_widget_host_view_base.cc
index 197960fed6152762e78077f530c6f6d935f43dc3..9d36c24a2864eacb699fb8374f8aca425c3eb61f 100644
--- a/content/browser/renderer_host/render_widget_host_view_base.cc
+++ b/content/browser/renderer_host/render_widget_host_view_base.cc
@@ -608,4 +608,12 @@ SkBitmap::Config RenderWidgetHostViewBase::PreferredReadbackFormat() {
   return SkBitmap::kARGB_8888_Config;
 }
 
+gfx::SizeF RenderWidgetHostViewBase::GetVisibleViewportSize() const {
+  return gfx::SizeF(GetViewBounds().width(), GetViewBounds().height());
+}
+
+void RenderWidgetHostViewBase::SetInsets(const gfx::Insets& insets) {
+  NOTIMPLEMENTED();
+}
+
 }  // namespace content