Added 'contextReady' message for HostPairingScreen.

Added 'contextReady' message for HostPairingScreen.

Sometimes the screen starts to send updates to JS part to early, when screen
is not registered yet. As a result several messages with context diffs could
be ignored, and JS context became inconsistent with C++ context. I added
'contextReady' message, that is send from JS when context is ready to recieve
updates. Before that the screen handler caches changes in the local context.

BUG=375191
Committed: https://crrev.com/b817eec554070b33011842ad9e4fc8185670dfc2
Cr-Commit-Position: refs/heads/master@{#295944}

[dzhioev (left Google), 2014-09-17 18:31:37]

dzhioev@chromium.org changed reviewers:
+ ygorshenin@chromium.org

[ygorshenin1, 2014-09-18 16:51:48]

Could you please also fill a bug for the CL?

https://codereview.chromium.org/581593003/diff/1/chrome/browser/ui/webui/chro...
File chrome/browser/ui/webui/chromeos/login/host_pairing_screen_handler.h
(right):

https://codereview.chromium.org/581593003/diff/1/chrome/browser/ui/webui/chro...
chrome/browser/ui/webui/chromeos/login/host_pairing_screen_handler.h:39: bool
context_ready_;
This name doesn't reflect the fact that it's JS part of the context is ready.
Could you please rename it to something like js_context_ready_?

[dzhioev (left Google), 2014-09-19 15:54:04]

> Could you please also fill a bug for the CL?
Attached to the existing bug.

https://codereview.chromium.org/581593003/diff/1/chrome/browser/ui/webui/chro...
File chrome/browser/ui/webui/chromeos/login/host_pairing_screen_handler.h
(right):

https://codereview.chromium.org/581593003/diff/1/chrome/browser/ui/webui/chro...
chrome/browser/ui/webui/chromeos/login/host_pairing_screen_handler.h:39: bool
context_ready_;
On 2014/09/18 16:51:48, ygorshenin1 wrote:
> This name doesn't reflect the fact that it's JS part of the context is ready.
> Could you please rename it to something like js_context_ready_?

Done.

[ygorshenin1, 2014-09-22 09:01:08]

lgtm

[dzhioev (left Google), 2014-09-22 09:04:39]

The CQ bit was checked by dzhioev@chromium.org

[commit-bot: I haz the power, 2014-09-22 09:05:43]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/581593003/20001

[commit-bot: I haz the power, 2014-09-22 09:48:52]

Committed patchset #2 (id:20001) as b973ecdc62610c3ad5c4fa20a9bc02dd7a281f37

[commit-bot: I haz the power, 2014-09-22 09:49:41]

Patchset 2 (id:??) landed as
https://crrev.com/b817eec554070b33011842ad9e4fc8185670dfc2
Cr-Commit-Position: refs/heads/master@{#295944}