Ignore should-scroll-on-main-thread if main frame is not scrollable

cc/layers/layer_impl.h

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_LAYERS_LAYER_IMPL_H_
 #define CC_LAYERS_LAYER_IMPL_H_
 
 #include <set>
 #include <string>
 
@@ skipping 380 matching lines @@
     return touch_event_handler_region_;
   }
 
   void SetDrawCheckerboardForMissingTiles(bool checkerboard) {
     draw_checkerboard_for_missing_tiles_ = checkerboard;
   }
   bool DrawCheckerboardForMissingTiles() const;
 
   InputHandler::ScrollStatus TryScroll(
       gfx::PointF screen_space_point,
-      InputHandler::ScrollInputType type) const;
+      InputHandler::ScrollInputType type,
+      bool main_frame_is_scrollable) const;
 
   void SetDoubleSided(bool double_sided);
   bool double_sided() const { return double_sided_; }
 
   void SetTransform(const gfx::Transform& transform);
   const gfx::Transform& transform() const { return transform_; }
   bool TransformIsAnimating() const;
   bool TransformIsAnimatingOnImplOnly() const;
 
   // Note this rect is in layer space (not content space).
@@ skipping 208 matching lines @@
   // Group of properties that need to be computed based on the layer tree
   // hierarchy before layers can be drawn.
   DrawProperties<LayerImpl, RenderSurfaceImpl> draw_properties_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_LAYER_IMPL_H_