Change cc::ElementId to be a uint64_t

cc/input/single_scrollbar_animation_controller_thinning_unittest.cc

 // Copyright 2013 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/input/single_scrollbar_animation_controller_thinning.h"
 
 #include "cc/layers/solid_color_scrollbar_layer_impl.h"
 #include "cc/test/fake_impl_task_runner_provider.h"
 #include "cc/test/fake_layer_tree_host_impl.h"
 #include "cc/test/geometry_test_utils.h"
@@ skipping 49 matching lines @@
         client_(&host_impl_) {}
 
  protected:
   const base::TimeDelta kThinningDuration = base::TimeDelta::FromSeconds(2);
 
   void SetUp() override {
     std::unique_ptr<LayerImpl> scroll_layer =
         LayerImpl::Create(host_impl_.active_tree(), 1);
     std::unique_ptr<LayerImpl> clip =
         LayerImpl::Create(host_impl_.active_tree(), 3);
-    scroll_layer->SetElementId(
-        LayerIdToElementIdForTesting(scroll_layer->id()));
+    scroll_layer->SetElementId(scroll_layer->id());
     clip_layer_ = clip.get();
     scroll_layer->SetScrollClipLayer(clip_layer_->id());
     LayerImpl* scroll_layer_ptr = scroll_layer.get();
 
     const int kId = 2;
     const int kThumbThickness = 10;
     const int kTrackStart = 0;
     const int kTrackLength = 100;
     const bool kIsLeftSideVerticalScrollbar = false;
     const bool kIsOverlayScrollbar = true;
@@ skipping 316 matching lines @@
                   scrollbar_layer_->thumb_thickness_scale_factor());
 
   time += kThinningDuration / 2;
   scrollbar_controller_->Animate(time);
   EXPECT_FLOAT_EQ(kIdleThicknessScale,
                   scrollbar_layer_->thumb_thickness_scale_factor());
 }
 
 }  // namespace
 }  // namespace cc