Replace overdraw_bottom_height with top_controls_layout_height.

cc/layers/layer_impl.cc

Index: cc/layers/layer_impl.cc
diff --git a/cc/layers/layer_impl.cc b/cc/layers/layer_impl.cc
index e6e60f5f3ef7cc1e474c2b5c4a2aef192906b3b7..ecc18e86118cb98ebe53524f321f999329d63d21 100644
--- a/cc/layers/layer_impl.cc
+++ b/cc/layers/layer_impl.cc
@@ -609,7 +609,7 @@ gfx::Vector2dF LayerImpl::FixedContainerSizeDelta() const {
   float scale_delta = layer_tree_impl()->page_scale_delta();
   float scale = layer_tree_impl()->page_scale_factor();
 
-  gfx::Vector2dF delta_from_scroll = scroll_clip_layer_->BoundsDelta();
+  gfx::Vector2dF delta_from_scroll = scroll_clip_layer_->bounds_delta();
   delta_from_scroll.Scale(1.f / scale);
 
   // The delta-from-pinch component requires some explanation: A viewport of
@@ -771,7 +771,8 @@ bool LayerImpl::IsActive() const {
 
 // TODO(wjmaclean) Convert so that bounds returns SizeF.
 gfx::Size LayerImpl::bounds() const {
-  return ToFlooredSize(temporary_impl_bounds_);
+  return gfx::ToFlooredSize(gfx::SizeF(bounds_.width() + bounds_delta_.x(),
+                                       bounds_.height() + bounds_delta_.y()));
 }
 
 void LayerImpl::SetBounds(const gfx::Size& bounds) {
@@ -779,7 +780,6 @@ void LayerImpl::SetBounds(const gfx::Size& bounds) {
     return;
 
   bounds_ = bounds;
-  temporary_impl_bounds_ = bounds;
 
   ScrollbarParametersDidChange();
   if (masks_to_bounds())
@@ -788,11 +788,11 @@ void LayerImpl::SetBounds(const gfx::Size& bounds) {
     NoteLayerPropertyChanged();
 }
 
-void LayerImpl::SetTemporaryImplBounds(const gfx::SizeF& bounds) {
-  if (temporary_impl_bounds_ == bounds)
+void LayerImpl::SetBoundsDelta(const gfx::Vector2dF& bounds_delta) {
+  if (bounds_delta_ == bounds_delta)
     return;
 
-  temporary_impl_bounds_ = bounds;
+  bounds_delta_ = bounds_delta;
 
   ScrollbarParametersDidChange();
   if (masks_to_bounds())
@@ -1274,8 +1274,7 @@ void LayerImpl::SetScrollbarPosition(ScrollbarLayerImplBase* scrollbar_layer,
     current_offset.Scale(layer_tree_impl()->total_page_scale_factor());
   }
 
-  scrollbar_layer->SetVerticalAdjust(
-      layer_tree_impl()->VerticalAdjust(scrollbar_clip_layer->id()));
+  scrollbar_layer->SetVerticalAdjust(scrollbar_clip_layer->bounds_delta().y());
   if (scrollbar_layer->orientation() == HORIZONTAL) {
     float visible_ratio = clip_rect.width() / scroll_rect.width();
     scrollbar_layer->SetCurrentPos(current_offset.x());