The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/8b4b5952c3259661772fb882053bbe67b9de2a67

commit 8b4b5952c3259661772fb882053bbe67b9de2a67
Author: dpapad <dpapad@chromium.org>
Date: Thu Mar 03 21:56:50 2016

WebUI: Allow rejecting a promise that is returned from cr.sendWithPromise().

 - Moving PromiseResolver helper class such that it can be used from cr.js
 - Updating cr.webUIResponse to accept an isSuccess parameter.
 - Renaming SettingsPageUIHandler#CallJavascriptCallback to
   ResolveJavascriptCallback, and adding new RejectJavascriptCallback method.
 - Adding test.

BUG= 591266 

Review URL: https://codereview.chromium.org/1758013002

Cr-Commit-Position: refs/heads/master@{#379104}

[modify] https://crrev.com/8b4b5952c3259661772fb882053bbe67b9de2a67/chrome/browser/ui/webui/settings/appearance_handler.cc
[modify] https://crrev.com/8b4b5952c3259661772fb882053bbe67b9de2a67/chrome/browser/ui/webui/settings/md_settings_ui.cc
[modify] https://crrev.com/8b4b5952c3259661772fb882053bbe67b9de2a67/chrome/browser/ui/webui/settings/md_settings_ui.h
[modify] https://crrev.com/8b4b5952c3259661772fb882053bbe67b9de2a67/chrome/browser/ui/webui/settings/search_engines_handler.cc
[modify] https://crrev.com/8b4b5952c3259661772fb882053bbe67b9de2a67/chrome/browser/ui/webui/settings/site_settings_handler.cc
[modify] https://crrev.com/8b4b5952c3259661772fb882053bbe67b9de2a67/chrome/test/data/webui/settings/cr_settings_browsertest.js
[modify] https://crrev.com/8b4b5952c3259661772fb882053bbe67b9de2a67/chrome/test/data/webui/webui_resource_async_browsertest.js
[modify] https://crrev.com/8b4b5952c3259661772fb882053bbe67b9de2a67/ui/webui/resources/html/cr.html
[add] https://crrev.com/8b4b5952c3259661772fb882053bbe67b9de2a67/ui/webui/resources/html/promise_resolver.html
[modify] https://crrev.com/8b4b5952c3259661772fb882053bbe67b9de2a67/ui/webui/resources/js/cr.js
[rename] https://crrev.com/8b4b5952c3259661772fb882053bbe67b9de2a67/ui/webui/resources/js/promise_resolver.js
[modify] https://crrev.com/8b4b5952c3259661772fb882053bbe67b9de2a67/ui/webui/resources/webui_resources.grd