[Cocoa] Tab audio mute control, behind a switch (off by default).

[Cocoa] Tab audio mute control, behind a switch (off by default).

This change renames MediaIndicatorView to MediaIndicatorButton, and then
merges-in the new functionality to support tab muting by clicking on the
indicator.  This is the "Cocoa port" of a previous change that added
this feature to the views UI: http://codereview.chromium.org/591963002

See change description in link above for details.

Also, this change resolves a long-standing bug where navigating back
into a NTP would leave the audio indicator turned on even though the NTP
does not emit sound.

BUG=360372, 344229
TEST=With --enable-tab-audio-muting, user can click audio indicator to toggle tab muting, or use the tab context menu to toggle muting of one or more selected tabs.

Committed: https://crrev.com/2178ec8cf854f0996a2d66649f52841e1ed18795
Cr-Commit-Position: refs/heads/master@{#302378}

[miu, 2014-10-28 23:04:56]

miu@chromium.org changed reviewers:
+ thakis@chromium.org

[miu, 2014-10-28 23:04:57]

thakis: Would you mind taking a look?

[miu, 2014-10-29 00:10:32]

https://codereview.chromium.org/688523002/diff/1/chrome/browser/ui/cocoa/tabs...
File chrome/browser/ui/cocoa/tabs/tab_strip_controller.mm (right):

https://codereview.chromium.org/688523002/diff/1/chrome/browser/ui/cocoa/tabs...
chrome/browser/ui/cocoa/tabs/tab_strip_controller.mm:1639: [[tabController
mediaIndicatorButton]
I just realized this is always causing the MediaIndicatorButton to be created,
but my intention was to create it only on first use (to save resources).  I've
got a simple solution, and just waiting for code to compile to test/confirm.  PS
2 coming soon...

[miu, 2014-10-29 00:32:15]

https://codereview.chromium.org/688523002/diff/1/chrome/browser/ui/cocoa/tabs...
File chrome/browser/ui/cocoa/tabs/tab_strip_controller.mm (right):

https://codereview.chromium.org/688523002/diff/1/chrome/browser/ui/cocoa/tabs...
chrome/browser/ui/cocoa/tabs/tab_strip_controller.mm:1639: [[tabController
mediaIndicatorButton]
On 2014/10/29 00:10:31, miu wrote:
> I just realized this is always causing the MediaIndicatorButton to be created,
> but my intention was to create it only on first use (to save resources).  I've
> got a simple solution, and just waiting for code to compile to test/confirm. 
PS
> 2 coming soon...

Done.

[Nico, 2014-10-31 21:55:00]

lgtm

https://codereview.chromium.org/688523002/diff/20001/chrome/browser/ui/cocoa/...
File chrome/browser/ui/cocoa/tabs/media_indicator_button.mm (right):

https://codereview.chromium.org/688523002/diff/20001/chrome/browser/ui/cocoa/...
chrome/browser/ui/cocoa/tabs/media_indicator_button.mm:78: nextState ==
TAB_MEDIA_STATE_NONE)) {
nit: this looks like model code that should be shared between different uis

[miu, 2014-11-01 00:43:39]

https://codereview.chromium.org/688523002/diff/20001/chrome/browser/ui/cocoa/...
File chrome/browser/ui/cocoa/tabs/media_indicator_button.mm (right):

https://codereview.chromium.org/688523002/diff/20001/chrome/browser/ui/cocoa/...
chrome/browser/ui/cocoa/tabs/media_indicator_button.mm:78: nextState ==
TAB_MEDIA_STATE_NONE)) {
On 2014/10/31 21:55:00, Nico wrote:
> nit: this looks like model code that should be shared between different uis

Yep.  Planning on some cleanup w.r.t. the animation logic in an upcoming change.
 (There were also some things in the views code that needed to wait on getting
the Mac impl done first.)

[miu, 2014-11-01 01:07:24]

The CQ bit was checked by miu@chromium.org

[commit-bot: I haz the power, 2014-11-01 01:08:04]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/688523002/20001

[commit-bot: I haz the power, 2014-11-01 01:59:13]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2014-11-01 01:59:56]

Patchset 2 (id:??) landed as
https://crrev.com/2178ec8cf854f0996a2d66649f52841e1ed18795
Cr-Commit-Position: refs/heads/master@{#302378}