Headless: expose WebPreferences to embedder, add --hide-scrollbars.

Headless: expose WebPreferences to embedder, add --hide-scrollbars.

Lets the embedder override WebPreferences for individual HeadlessBrowserContexts. Used to add back the --hide-scrollbars flag to headless_shell.

BUG=546953
Committed: https://crrev.com/d71fc504213b7d60f98d8b1db9abb6bda280a042
Cr-Commit-Position: refs/heads/master@{#422074}

[Eric Seckler, 2016-09-28 16:57:58]

Description was changed from

==========
Headless: expose WebPreferences to embedder, add --hide-scrollbars.

BUG=546953
==========

to

==========
Headless: expose WebPreferences to embedder, add --hide-scrollbars.

Lets the embedder override WebPreferences for individual
HeadlessBrowserContexts. Used to add back the --hide-scrollbars flag to
headless_shell.

BUG=546953
==========

[Eric Seckler, 2016-09-28 16:57:58]

eseckler@chromium.org changed reviewers:
+ skyostil@chromium.org

[Eric Seckler, 2016-09-28 16:59:30]

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

[commit-bot: I haz the power, 2016-09-28 16:59:49]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Eric Seckler, 2016-09-28 17:02:16]

I'm adding this as a per-BrowserContext-only option. Wasn't sure if it makes
sense to support setting a "default" callback in HeadlessBrowser::Options, or if
that's more confusing than useful ... :)

[commit-bot: I haz the power, 2016-09-28 17:15:15]

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

[commit-bot: I haz the power, 2016-09-28 17:15:16]

Dry run: This issue passed the CQ dry run.

[Sami, 2016-09-29 09:38:26]

Per-context seems like a good choice to me. Could you add a test for overriding
the options too?

https://codereview.chromium.org/2374063002/diff/1/headless/public/headless_br...
File headless/public/headless_browser_context.h (right):

https://codereview.chromium.org/2374063002/diff/1/headless/public/headless_br...
headless/public/headless_browser_context.h:106: // created within this
HeadlessBrowserContext.
This is called on the browser main thread, right? And possibly multiple times?

https://codereview.chromium.org/2374063002/diff/1/headless/public/headless_br...
headless/public/headless_browser_context.h:111:
std::function<void(WebPreferences*)> callback);
This should probably be a base::Callback since most of Chrome is still built
that way.

[Eric Seckler, 2016-09-30 09:17:51]

Thanks! Added a test as well.

https://codereview.chromium.org/2374063002/diff/1/headless/public/headless_br...
File headless/public/headless_browser_context.h (right):

https://codereview.chromium.org/2374063002/diff/1/headless/public/headless_br...
headless/public/headless_browser_context.h:106: // created within this
HeadlessBrowserContext.
On 2016/09/29 09:38:26, Sami wrote:
> This is called on the browser main thread, right? And possibly multiple times?

It's definitely called multiple times (whenever the prefs of a RenderView
change). It looks like OverrideWebkitPrefs is executed on the browser main
thread and you don't have to worry about it being called by different threads,
but I also can't find anything explicitly confirming this.

Added a comment to these effects.

https://codereview.chromium.org/2374063002/diff/1/headless/public/headless_br...
headless/public/headless_browser_context.h:111:
std::function<void(WebPreferences*)> callback);
On 2016/09/29 09:38:26, Sami wrote:
> This should probably be a base::Callback since most of Chrome is still built
> that way.

Done.

[Eric Seckler, 2016-09-30 09:33:56]

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

[commit-bot: I haz the power, 2016-09-30 09:34:11]

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, 2016-09-30 09:42:27]

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

[commit-bot: I haz the power, 2016-09-30 09:42:28]

Dry run: This issue passed the CQ dry run.

[Sami, 2016-09-30 10:00:51]

lgtm, thanks!

[Eric Seckler, 2016-09-30 10:03:00]

The CQ bit was checked by eseckler@chromium.org

[commit-bot: I haz the power, 2016-09-30 10:03:12]

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, 2016-09-30 10:08:21]

Description was changed from

==========
Headless: expose WebPreferences to embedder, add --hide-scrollbars.

Lets the embedder override WebPreferences for individual
HeadlessBrowserContexts. Used to add back the --hide-scrollbars flag to
headless_shell.

BUG=546953
==========

to

==========
Headless: expose WebPreferences to embedder, add --hide-scrollbars.

Lets the embedder override WebPreferences for individual
HeadlessBrowserContexts. Used to add back the --hide-scrollbars flag to
headless_shell.

BUG=546953
==========

[commit-bot: I haz the power, 2016-09-30 10:08:22]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-09-30 10:10:34]

Description was changed from

==========
Headless: expose WebPreferences to embedder, add --hide-scrollbars.

Lets the embedder override WebPreferences for individual
HeadlessBrowserContexts. Used to add back the --hide-scrollbars flag to
headless_shell.

BUG=546953
==========

to

==========
Headless: expose WebPreferences to embedder, add --hide-scrollbars.

Lets the embedder override WebPreferences for individual
HeadlessBrowserContexts. Used to add back the --hide-scrollbars flag to
headless_shell.

BUG=546953

Committed: https://crrev.com/d71fc504213b7d60f98d8b1db9abb6bda280a042
Cr-Commit-Position: refs/heads/master@{#422074}
==========

[commit-bot: I haz the power, 2016-09-30 10:10:35]

Patchset 2 (id:??) landed as
https://crrev.com/d71fc504213b7d60f98d8b1db9abb6bda280a042
Cr-Commit-Position: refs/heads/master@{#422074}