Suppress scrollbar animation if the scroll gesture does not scroll

cc/layers/layer_impl.cc

 // 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.
 
 #include "cc/layers/layer_impl.h"
 
 #include "base/debug/trace_event.h"
 #include "base/strings/stringprintf.h"
 #include "cc/animation/animation_registrar.h"
 #include "cc/animation/scrollbar_animation_controller.h"
@@ skipping 957 matching lines @@
     vertical_scrollbar_layer_->SetCurrentPos(current_offset.y());
     vertical_scrollbar_layer_->SetMaximum(max_scroll_offset_.y());
     vertical_scrollbar_layer_->SetVisibleToTotalLengthRatio(
         viewport.height() / scrollable_size.height());
   }
 
   if (current_offset == last_scroll_offset_)
     return;
   last_scroll_offset_ = current_offset;
 
-  if (scrollbar_animation_controller_ &&
-      !scrollbar_animation_controller_->IsScrollGestureInProgress()) {
-    scrollbar_animation_controller_->DidProgrammaticallyUpdateScroll(
+  if (scrollbar_animation_controller_) {
+    scrollbar_animation_controller_->DidScrollUpdate(
         layer_tree_impl_->CurrentPhysicalTimeTicks());
   }
 
   // Get the current_offset_.y() value for a sanity-check on scrolling
   // benchmark metrics. Specifically, we want to make sure
   // BasicMouseWheelSmoothScrollGesture has proper scroll curves.
   if (layer_tree_impl()->IsActiveTree()) {
     TRACE_COUNTER_ID1("gpu", "scroll_offset_y", this->id(), current_offset.y());
   }
 }
@@ skipping 316 matching lines @@
 
 size_t LayerImpl::GPUMemoryUsageInBytes() const { return 0; }
 
 scoped_ptr<base::Value> LayerImpl::AsValue() const {
   scoped_ptr<base::DictionaryValue> state(new base::DictionaryValue());
   AsValueInto(state.get());
   return state.PassAs<base::Value>();
 }
 
 }  // namespace cc