[vr] Make name of trace event clearer

Bug: 788786
Cq-Include-Trybots: master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_vr;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
Change-Id: Ibc2561c3301060fa8a05289bfd581d7492962957
Reviewed-on: https://chromium-review.googlesource.com/909716Reviewed-by: Ian Vollick <vollick@chromium.org>
Commit-Queue: Tibor Goldschwendt <tiborg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#535881}

chrome/browser/vr/ui_scene.cc

@@ -80,7 +80,7 @@ bool UiScene::OnBeginFrame(const base::TimeTicks& current_time,
   }
 
   {
-    TRACE_EVENT0("gpu", "UiScene::OnBeginFrame.UpdateAnimations");
+    TRACE_EVENT0("gpu", "UiScene::OnBeginFrame.UpdateAnimationsAndOpacity");
 
     // Process all animations and pre-binding work. I.e., induce any
     // time-related "dirtiness" on the scene graph.