Files app: Work around the issue about opening menus by keeping references to <hr>s.

Files app: Work around the issue about opening menus by keeping references to <hr>s.

Files app's settings menu uses cr.ui.Menu, and <hr>s in the menu needs to be
decorated by cr.ui.MenuItem. However, in some cases, the <hr>s can lose the
decorated functions for some reason (suspected that it's by GC for <hr> wrappers).
This behavior be worked around by explicitly keeping reference to those <hr>s.

BUG=689255
TEST=confirmed 300+ trials of repro step did not reproduce the issue. It reproduced around 10% without the patch.
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation
TBR=oka@chromium.org

Review-Url: https://codereview.chromium.org/2712403003
Cr-Commit-Position: refs/heads/master@{#453557}
(cherry picked from commit 3bc177a7e5b7d15e6635613373ac316263576150)

Review-Url: https://codereview.chromium.org/2728573003 .
Cr-Commit-Position: refs/branch-heads/2987@{#736}
Cr-Branched-From: ad51088c0e8776e8dcd963dbe752c4035ba6dab6-refs/heads/master@{#444943}
Committed: https://chromium.googlesource.com/chromium/src/+/d26dc12aebd14b71b72081877682a97d11047652

[fukino, 2017-03-02 02:35:29]

Description was changed from

==========
Files app: Work around the issue about opening menus by keeping references to
<hr>s.

Files app's settings menu uses cr.ui.Menu, and <hr>s in the menu needs to be
decorated by cr.ui.MenuItem. However, in some cases, the <hr>s can lose the
decorated functions for some reason (suspected that it's by GC for <hr>
wrappers).
This behavior be worked around by explicitly keeping reference to those <hr>s.

BUG=689255
TEST=confirmed 300+ trials of repro step did not reproduce the issue. It
reproduced around 10% without the patch.
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation
TBR=oka@chromium.org

Review-Url: https://codereview.chromium.org/2712403003
Cr-Commit-Position: refs/heads/master@{#453557}
(cherry picked from commit 3bc177a7e5b7d15e6635613373ac316263576150)
==========

to

==========
Files app: Work around the issue about opening menus by keeping references to
<hr>s.

Files app's settings menu uses cr.ui.Menu, and <hr>s in the menu needs to be
decorated by cr.ui.MenuItem. However, in some cases, the <hr>s can lose the
decorated functions for some reason (suspected that it's by GC for <hr>
wrappers).
This behavior be worked around by explicitly keeping reference to those <hr>s.

BUG=689255
TEST=confirmed 300+ trials of repro step did not reproduce the issue. It
reproduced around 10% without the patch.
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation
TBR=oka@chromium.org

Review-Url: https://codereview.chromium.org/2712403003
Cr-Commit-Position: refs/heads/master@{#453557}
(cherry picked from commit 3bc177a7e5b7d15e6635613373ac316263576150)

Review-Url: https://codereview.chromium.org/2728573003 .
Cr-Commit-Position: refs/branch-heads/2987@{#736}
Cr-Branched-From:
ad51088c0e8776e8dcd963dbe752c4035ba6dab6-refs/heads/master@{#444943}
Committed:
https://chromium.googlesource.com/chromium/src/+/d26dc12aebd14b71b72081877682...
==========

[fukino, 2017-03-02 02:35:31]

Committed patchset #1 (id:1) manually as
d26dc12aebd14b71b72081877682a97d11047652.