Remove the use of KeyEvent.keyIdentifier.

ui/file_manager/file_manager/background/js/test_util.js

Index: ui/file_manager/file_manager/background/js/test_util.js
diff --git a/ui/file_manager/file_manager/background/js/test_util.js b/ui/file_manager/file_manager/background/js/test_util.js
index 12f882e370f4dea50700d2c72846a884de18b68c..aa2a5480056212b0fbc4baaa56d8d928f16309e0 100644
--- a/ui/file_manager/file_manager/background/js/test_util.js
+++ b/ui/file_manager/file_manager/background/js/test_util.js
@@ -187,7 +187,7 @@ test.util.sync.copyFile = function(contentWindow, filename) {
     return false;
   // Ctrl+C and Ctrl+V
   test.util.sync.fakeKeyDown(
-      contentWindow, '#file-list', 'w', 'U+0043', true, false, false);
+      contentWindow, '#file-list', 'c', 'U+0043', true, false, false);

[oka, 2016/06/09 13:32:31]

Can you remove keyIdentifier from fakeKeyDown?

[fukino, 2016/06/09 13:47:50]

As the cr.ui.Command still depends on keyIdentifier property of the event
object, so we need it right now.
I'll remove it once we remove the dependency from cr.ui.Command.

   test.util.sync.fakeKeyDown(
       contentWindow, '#file-list', 'v', 'U+0056', true, false, false);
   return true;