Revert of "Converted LayerImpl::bounds() to return SizeF."

cc/layers/layer_impl.h

Index: cc/layers/layer_impl.h
diff --git a/cc/layers/layer_impl.h b/cc/layers/layer_impl.h
index 54dda06fc2d417d2b8e5503f899c5f98cb1a37dd..1e8fa63d3f5ef29db059bd1ec911522a361afb66 100644
--- a/cc/layers/layer_impl.h
+++ b/cc/layers/layer_impl.h
@@ -364,7 +364,7 @@ class CC_EXPORT LayerImpl : public LayerAnimationValueObserver,
   // them from the other values.
 
   void SetBounds(const gfx::Size& bounds);
-  gfx::SizeF bounds() const;
+  gfx::Size bounds() const;
   void SetBoundsDelta(const gfx::Vector2dF& bounds_delta);
   gfx::Vector2dF bounds_delta() const { return bounds_delta_; }
 
@@ -515,6 +515,9 @@ class CC_EXPORT LayerImpl : public LayerAnimationValueObserver,
   void RemoveScrollbar(ScrollbarLayerImplBase* layer);
   bool HasScrollbar(ScrollbarOrientation orientation) const;
   void ScrollbarParametersDidChange(bool on_resize);
+  int clip_height() {
+    return scroll_clip_layer_ ? scroll_clip_layer_->bounds().height() : 0;
+  }
 
   gfx::Rect LayerRectToContentRect(const gfx::RectF& layer_rect) const;