media: Support simultaneous permission requests from multiple WebContents in ProtectedMediaIdentifi…

media: Support simultaneous permission requests from multiple WebContents in ProtectedMediaIdentifierPermissionContext.

ProtectedMediaIdentifierPermissionContext is shared by multiple WebContents.
Even though we don't support multiple permission requests from the same page
(WebContents), we should support permission requests from multiple WebContents.

Test step:
1. Make sure no allowed or blocked exception in content settings.
2. Open a tab/extension, navigate to a page that requests permission. A prompt
should appear. Don't do anything.
3. Open another tab/extension, navigate to a page that requests permission. A
prompt should also appear.
4. Play with allow/block/dismiss and see whether permission status is as
expected and whether content settings are updated correctly.

BUG=446263
TEST=See above.

Committed: https://crrev.com/473ff67794aa0dd775a461a30750aaa7a1116681
Cr-Commit-Position: refs/heads/master@{#314933}

[xhwang, 2015-02-05 23:20:51]

xhwang@chromium.org changed reviewers:
+ ddorwin@chromium.org, mukai@chromium.org

[xhwang, 2015-02-05 23:20:51]

xhwang@chromium.org changed required reviewers:
+ ddorwin@chromium.org

[xhwang, 2015-02-05 23:20:52]

PTAL, thanks!

[ddorwin, 2015-02-05 23:34:46]

LGTM with comments.

https://codereview.chromium.org/903873002/diff/1/chrome/browser/media/protect...
File chrome/browser/media/protected_media_identifier_permission_context.cc
(right):

https://codereview.chromium.org/903873002/diff/1/chrome/browser/media/protect...
chrome/browser/media/protected_media_identifier_permission_context.cc:119: if
(!pending_requests_.count(web_contents))
Redundant with the first part of line 123?

https://codereview.chromium.org/903873002/diff/1/chrome/browser/media/protect...
chrome/browser/media/protected_media_identifier_permission_context.cc:123: if
(request == pending_requests_.end() || !request->second.second.Equals(id))
Why would the IDs not be equal?

https://codereview.chromium.org/903873002/diff/1/chrome/browser/media/protect...
chrome/browser/media/protected_media_identifier_permission_context.cc:187: //
The request may have been canceled. Drop the callback then.
nit: s/then/in that case/ or something like that

[xhwang, 2015-02-06 00:20:55]

New patchsets have been uploaded after l-g-t-m from ddorwin@chromium.org

[xhwang, 2015-02-06 00:21:47]

https://codereview.chromium.org/903873002/diff/1/chrome/browser/media/protect...
File chrome/browser/media/protected_media_identifier_permission_context.cc
(right):

https://codereview.chromium.org/903873002/diff/1/chrome/browser/media/protect...
chrome/browser/media/protected_media_identifier_permission_context.cc:119: if
(!pending_requests_.count(web_contents))
On 2015/02/05 23:34:46, ddorwin wrote:
> Redundant with the first part of line 123?

Done.

https://codereview.chromium.org/903873002/diff/1/chrome/browser/media/protect...
chrome/browser/media/protected_media_identifier_permission_context.cc:123: if
(request == pending_requests_.end() || !request->second.second.Equals(id))
On 2015/02/05 23:34:46, ddorwin wrote:
> Why would the IDs not be equal?

I don't that'll happen in practice. But it's possible that the first request is
made and pending, then a second request is made and rejected. But before the
second callback is received (e.g. posted), CancelPermissionRequest() is called
to cancel the second one.

https://codereview.chromium.org/903873002/diff/1/chrome/browser/media/protect...
chrome/browser/media/protected_media_identifier_permission_context.cc:187: //
The request may have been canceled. Drop the callback then.
On 2015/02/05 23:34:46, ddorwin wrote:
> nit: s/then/in that case/ or something like that

Done.

[ddorwin, 2015-02-06 00:38:29]

The CQ bit was checked by ddorwin@chromium.org

[commit-bot: I haz the power, 2015-02-06 00:40:02]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/903873002/40001

[commit-bot: I haz the power, 2015-02-06 01:05:06]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-02-06 01:07:30]

Patchset 3 (id:??) landed as
https://crrev.com/473ff67794aa0dd775a461a30750aaa7a1116681
Cr-Commit-Position: refs/heads/master@{#314933}