Fixed position layer counter-scroll with main thread scroll offset fractional part

cc/layers/layer_impl.cc

 // Copyright 2012 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/debug/trace_event_argument.h"
 #include "base/json/json_reader.h"
 #include "base/strings/stringprintf.h"
@@ skipping 533 matching lines @@
 
   // Save the difference but clear the sent delta so that we don't subtract
   // it again in SetScrollOffsetAndDelta's pending twin mirroring logic.
   gfx::Vector2dF remaining_delta =
       layer_animation_controller_->scroll_offset_animation_was_interrupted()
           ? gfx::Vector2dF()
           : layer->ScrollDelta() - layer->sent_scroll_delta();
 
   layer->SetSentScrollDelta(gfx::Vector2dF());
   layer->SetScrollOffsetAndDelta(scroll_offset_, remaining_delta);
+  layer->SetMainScrollOffsetFractionalPart(main_scroll_offset_fractional_part_);
 
   layer->Set3dSortingContextId(sorting_context_id_);
   layer->SetNumDescendantsThatDrawContent(num_descendants_that_draw_content_);
 
   LayerImpl* scroll_parent = nullptr;
   if (scroll_parent_) {
     scroll_parent = layer->layer_tree_impl()->LayerById(scroll_parent_->id());
     DCHECK(scroll_parent);
   }
 
@@ skipping 1044 matching lines @@
   SetNeedsPushProperties();
   layer_tree_impl()->set_needs_update_draw_properties();
   if (should_have_render_surface) {
     render_surface_ = make_scoped_ptr(new RenderSurfaceImpl(this));
     return;
   }
   render_surface_.reset();
 }
 
 }  // namespace cc