https://codereview.chromium.org/2269143004/ targets for M54, same as internal bug target.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a9d42b7e1ef639e0a29462046e543561ca37230a

commit a9d42b7e1ef639e0a29462046e543561ca37230a
Author: xiyuan <xiyuan@chromium.org>
Date: Wed Aug 24 23:07:36 2016

arc: Update notification close button image

Update the close button image and fix tapping-not-working issue
since making changes to the file.

BUG= 640399 
BUG=b/30814819
BUG=b/30917629
TEST=Manual. Verify new close button image on arc notifications.
    And tapping to close works.

Review-Url: https://codereview.chromium.org/2269143004
Cr-Commit-Position: refs/heads/master@{#414188}

[modify] https://crrev.com/a9d42b7e1ef639e0a29462046e543561ca37230a/ui/arc/notification/arc_custom_notification_view.cc
[add] https://crrev.com/a9d42b7e1ef639e0a29462046e543561ca37230a/ui/resources/default_100_percent/common/arc_notification_close.png
[add] https://crrev.com/a9d42b7e1ef639e0a29462046e543561ca37230a/ui/resources/default_200_percent/common/arc_notification_close.png
[modify] https://crrev.com/a9d42b7e1ef639e0a29462046e543561ca37230a/ui/resources/ui_resources.grd

Approving merge to M53 cros.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/9e6c9dd34006642d4e52fa9d90be41d11a4c8243

commit 9e6c9dd34006642d4e52fa9d90be41d11a4c8243
Author: Xiyuan Xia <xiyuan@google.com>
Date: Thu Aug 25 20:06:43 2016

Merge "arc: Update notification close button image"

> Update the close button image and fix tapping-not-working issue
> since making changes to the file.
>
> BUG= 640399 
> BUG=b/30814819
> BUG=b/30917629
> TEST=Manual. Verify new close button image on arc notifications.
>     And tapping to close works.
>
> Review-Url: https://codereview.chromium.org/2269143004
> Cr-Commit-Position: refs/heads/master@{#414188}
> (cherry picked from commit a9d42b7e1ef639e0a29462046e543561ca37230a)

Review URL: https://codereview.chromium.org/2273133003 .

Cr-Commit-Position: refs/branch-heads/2785@{#752}
Cr-Branched-From: 68623971be0cfc492a2cb0427d7f478e7b214c24-refs/heads/master@{#403382}

[modify] https://crrev.com/9e6c9dd34006642d4e52fa9d90be41d11a4c8243/ui/arc/notification/arc_custom_notification_view.cc
[add] https://crrev.com/9e6c9dd34006642d4e52fa9d90be41d11a4c8243/ui/resources/default_100_percent/common/arc_notification_close.png
[add] https://crrev.com/9e6c9dd34006642d4e52fa9d90be41d11a4c8243/ui/resources/default_200_percent/common/arc_notification_close.png
[modify] https://crrev.com/9e6c9dd34006642d4e52fa9d90be41d11a4c8243/ui/resources/ui_resources.grd