[ios] Remove IDC_CLOSE_TAB

[ios] Remove IDC_CLOSE_TAB

This CL removes the IDC_CLOSE_TAB command ID and replaces all uses of it with 
calls to a command dispatcher.

In order to do that, the following infrastructural changes are also made:

- A BrowserCommands protocol is created that will house all of the ChromeCommands
handled by the BVC.

- The BVC's _dispatcher is exposed publicly as an id<BrowserCommands>

- Various other classes that accepted the BVC's dispatcher have BrowsreCommands
added to the protocols that dispatcher conforms to.

- An egtest utility to get the dispatcher for the main BVC is added, and will be used to
replace calls to RunCommandWithActiveViewController(). 

BUG=738881
TEST=Manually tested closing tabs.

[marq (ping after 24h), 2017-06-30 16:33:22]

The CQ bit was checked by marq@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-06-30 16:33:35]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-06-30 16:45:07]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-06-30 16:45:08]

Dry run: Try jobs failed on following builders:
  ios-simulator on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator/bui...)
  ios-simulator-xcode-clang on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator-xco...)

[marq (ping after 24h), 2017-07-03 07:38:09]

Fix unit test.

[marq (ping after 24h), 2017-07-03 07:38:30]

The CQ bit was checked by marq@chromium.org

[marq (ping after 24h), 2017-07-03 07:38:34]

The CQ bit was unchecked by marq@chromium.org

[marq (ping after 24h), 2017-07-03 07:38:41]

The CQ bit was checked by marq@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-07-03 07:38:52]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[marq (ping after 24h), 2017-07-03 09:18:08]

Self review.

[marq (ping after 24h), 2017-07-03 09:22:17]

Description was changed from

==========
[ios] Remove IDC_CLOSE_TAB

BUG=
==========

to

==========
[ios] Remove IDC_CLOSE_TAB

This CL removes the IDC_CLOSE_TAB command ID and replaces all uses of it with 
calls to a command dispatcher.

In order to do that, the following infrastructural changes are also made:

- A BrowserCommands protocol is created that will house all of the
ChromeCommands
handled by the BVC.

- The BVC's _dispatcher is exposed publicly as an id<BrowserCommands>

- Various other classes that accepted the BVC's dispatcher have BrowsreCommands
added to the protocols that dispatcher conforms to.

- An egtest utility to get the dispatcher for the main BVC is added, and will be
used to
replace calls to RunCommandWithActiveViewController(). 

BUG=
==========

[marq (ping after 24h), 2017-07-03 09:23:45]

Add comment for chrome_test_util.h"

[marq (ping after 24h), 2017-07-03 13:29:17]

Description was changed from

==========
[ios] Remove IDC_CLOSE_TAB

This CL removes the IDC_CLOSE_TAB command ID and replaces all uses of it with 
calls to a command dispatcher.

In order to do that, the following infrastructural changes are also made:

- A BrowserCommands protocol is created that will house all of the
ChromeCommands
handled by the BVC.

- The BVC's _dispatcher is exposed publicly as an id<BrowserCommands>

- Various other classes that accepted the BVC's dispatcher have BrowsreCommands
added to the protocols that dispatcher conforms to.

- An egtest utility to get the dispatcher for the main BVC is added, and will be
used to
replace calls to RunCommandWithActiveViewController(). 

BUG=
==========

to

==========
[ios] Remove IDC_CLOSE_TAB

This CL removes the IDC_CLOSE_TAB command ID and replaces all uses of it with 
calls to a command dispatcher.

In order to do that, the following infrastructural changes are also made:

- A BrowserCommands protocol is created that will house all of the
ChromeCommands
handled by the BVC.

- The BVC's _dispatcher is exposed publicly as an id<BrowserCommands>

- Various other classes that accepted the BVC's dispatcher have BrowsreCommands
added to the protocols that dispatcher conforms to.

- An egtest utility to get the dispatcher for the main BVC is added, and will be
used to
replace calls to RunCommandWithActiveViewController(). 

BUG=738881
==========

[marq (ping after 24h), 2017-07-04 09:26:06]

Description was changed from

==========
[ios] Remove IDC_CLOSE_TAB

This CL removes the IDC_CLOSE_TAB command ID and replaces all uses of it with 
calls to a command dispatcher.

In order to do that, the following infrastructural changes are also made:

- A BrowserCommands protocol is created that will house all of the
ChromeCommands
handled by the BVC.

- The BVC's _dispatcher is exposed publicly as an id<BrowserCommands>

- Various other classes that accepted the BVC's dispatcher have BrowsreCommands
added to the protocols that dispatcher conforms to.

- An egtest utility to get the dispatcher for the main BVC is added, and will be
used to
replace calls to RunCommandWithActiveViewController(). 

BUG=738881
==========

to

==========
[ios] Remove IDC_CLOSE_TAB

This CL removes the IDC_CLOSE_TAB command ID and replaces all uses of it with 
calls to a command dispatcher.

In order to do that, the following infrastructural changes are also made:

- A BrowserCommands protocol is created that will house all of the
ChromeCommands
handled by the BVC.

- The BVC's _dispatcher is exposed publicly as an id<BrowserCommands>

- Various other classes that accepted the BVC's dispatcher have BrowsreCommands
added to the protocols that dispatcher conforms to.

- An egtest utility to get the dispatcher for the main BVC is added, and will be
used to
replace calls to RunCommandWithActiveViewController(). 

BUG=738881
TEST=Manually tested closing tabs.
==========