Forward {Will/Did}StartBrowser calls to page test

Forward {Will/Did}StartBrowser calls to page test

Now, WillStartBrowser method is never called on the benchmark tests.
This patch override the stub PageTest.WillStartBrowser in
RecorderPageTest. When WillStartBrowser is called, it forwards the call
to it's benchmark test.

The same behaviour is also applied to DidStartBrowser method

R=
BUG=400894
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=290684

[ariblue, 2014-08-05 23:50:19]

I've got a very similar patch here: https://codereview.chromium.org/427093002/
that was reverted at the end of last week (looks like due to an unrelated
telemetry test failure). I'd be fine with either of these going through. lgtm.

[tonyg, 2014-08-06 01:43:50]

lgtm

[commit-bot: I haz the power, 2014-08-06 01:46:09]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/a.renevier@samsung.com/447633002/1

[commit-bot: I haz the power, 2014-08-06 06:15:30]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  linux_chromium_rel_swarming on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)
  mac_chromium_compile_dbg on tryserver.chromium.mac
(http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_comp...)

[commit-bot: I haz the power, 2014-08-06 08:05:29]

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

[commit-bot: I haz the power, 2014-08-06 08:05:30]

Try jobs failed on following builders:
  linux_chromium_rel_swarming on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[a.renevier, 2014-08-06 19:54:54]

On 2014/08/06 08:05:30, I haz the power (commit-bot) wrote:
> Try jobs failed on following builders:
>   linux_chromium_rel_swarming on tryserver.chromium.linux
>
(http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

I don't really understand which is failing.

[ariblue, 2014-08-19 21:09:08]

The CQ bit was checked by ariblue@google.com

[ariblue, 2014-08-19 21:09:08]

lgtm

This should land, the error was likely unrelated.

[commit-bot: I haz the power, 2014-08-19 21:10:28]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/a.renevier@samsung.com/447633002/1

[commit-bot: I haz the power, 2014-08-19 22:51:40]

Committed patchset #1 (1) as 290684