Change cc::ElementId to be a uint64_t

cc/input/scrollbar_animation_controller_unittest.cc

Index: cc/input/scrollbar_animation_controller_unittest.cc
diff --git a/cc/input/scrollbar_animation_controller_unittest.cc b/cc/input/scrollbar_animation_controller_unittest.cc
index 07ae92a47a79fb20b07d551c8e161f3de11b65d5..6ac0394a70387d2f25b46f1689b909267341ecd6 100644
--- a/cc/input/scrollbar_animation_controller_unittest.cc
+++ b/cc/input/scrollbar_animation_controller_unittest.cc
@@ -80,8 +80,9 @@ class ScrollbarAnimationControllerAuraOverlayTest : public testing::Test {
     std::unique_ptr<LayerImpl> clip =
         LayerImpl::Create(host_impl_.active_tree(), 2);
     clip_layer_ = clip.get();
-    scroll_layer->SetElementId(
-        LayerIdToElementIdForTesting(scroll_layer->id()));
+    ElementId element_id;
+    element_id.id = scroll_layer->id();

[wkorman, 2017/05/08 18:23:24]

In subsequent change we could consider adding a TestElementId that allows
setting via ctor to reduce LOC in tests.

+    scroll_layer->SetElementId(element_id);
     scroll_layer->SetScrollClipLayer(clip_layer_->id());
     LayerImpl* scroll_layer_ptr = scroll_layer.get();
 
@@ -1245,8 +1246,9 @@ class ScrollbarAnimationControllerAndroidTest
     std::unique_ptr<LayerImpl> clip =
         LayerImpl::Create(host_impl_.active_tree(), 3);
     clip_layer_ = clip.get();
-    scroll_layer->SetElementId(
-        LayerIdToElementIdForTesting(scroll_layer->id()));
+    ElementId element_id;
+    element_id.id = scroll_layer->id();
+    scroll_layer->SetElementId(element_id);
 
     scroll_layer->SetScrollClipLayer(clip_layer_->id());
     LayerImpl* scroll_layer_ptr = scroll_layer.get();