Set cc::Display visibility to false when going to the background.

Set cc::Display visibility to false when going to the background.

This visibility notification path was unhooked at some point during the
refactoring to split into layer/display compositor in the last year or
two.  It was rehooked but only for Aura in
https://codereview.chromium.org/2238693002, leaving Android with
visibility permanently true on the display compositor.

BUG=728885

[aelias_OOO_until_Jul13, 2017-06-02 00:27:04]

aelias@chromium.org changed reviewers:
+ boliu@chromium.org

[aelias_OOO_until_Jul13, 2017-06-02 00:27:26]

Hi Bo, PTAL.

[aelias_OOO_until_Jul13, 2017-06-02 00:29:35]

Description was changed from

==========
Set cc::Display visibility to false when going to the background.

This visibility notification path was unhooked at some point during the
refactoring to split into layer/surfaces compositor in the last year or
two.  It was rehooked but only for Aura in
https://codereview.chromium.org/2238693002, leaving Android with
visibility permanently true on the root display compositor.

BUG=728885
==========

to

==========
Set cc::Display visibility to false when going to the background.

This visibility notification path was unhooked at some point during the
refactoring to split into layer/surfaces compositor in the last year or
two.  It was rehooked but only for Aura in
https://codereview.chromium.org/2238693002, leaving Android with
visibility permanently true on the display compositor.

BUG=728885
==========

[aelias_OOO_until_Jul13, 2017-06-02 00:29:44]

Description was changed from

==========
Set cc::Display visibility to false when going to the background.

This visibility notification path was unhooked at some point during the
refactoring to split into layer/surfaces compositor in the last year or
two.  It was rehooked but only for Aura in
https://codereview.chromium.org/2238693002, leaving Android with
visibility permanently true on the display compositor.

BUG=728885
==========

to

==========
Set cc::Display visibility to false when going to the background.

This visibility notification path was unhooked at some point during the
refactoring to split into layer/display compositor in the last year or
two.  It was rehooked but only for Aura in
https://codereview.chromium.org/2238693002, leaving Android with
visibility permanently true on the display compositor.

BUG=728885
==========

[boliu, 2017-06-02 00:30:35]

https://codereview.chromium.org/2918023002/diff/1/content/browser/renderer_ho...
File content/browser/renderer_host/compositor_impl_android.cc (right):

https://codereview.chromium.org/2918023002/diff/1/content/browser/renderer_ho...
content/browser/renderer_host/compositor_impl_android.cc:568: display_.reset();
we reset the display a few lines below, does this code really matter?

[aelias_OOO_until_Jul13, 2017-06-02 01:13:57]

Yeah, OK, it doesn't do anything extra compared to the destructors except call
DiscardBackbufferCHROMIUM, which is otherwise released anyway, so closing this.