Don't send the renderer flags that it doesn't use.

BUG=314909

Review URL: https://codereview.chromium.org/57463011

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@233542 0039d316-1c4b-4281-b951-d872f2087c98
Reland: [Telemetry] Fix image_decoding_measurement timeout.

This was reverted because it caused some timeouts. The reland is the same as the
original but I now preseved the original timeout values of Page.enable and
Page.disable.

> util.WaitFor polls which is not appropriate for PerformActionAndWaitForNavigate.
>
> Since DispatchNotifications blocks in recv until it gets some data, there is no
> need to poll at an interval. Instead, we should call recv again as soon as
> possible after dispatching a notification.
>
> In the case of the image decoding measurement, it runs timeline recording. There
> were so many timeline messages to receive that we were not always getting to the
> important Page.navigate message before timing out.
>
> Example:
> http://build.chromium.org/p/chromium.perf/builders/Linux%20Perf%20%281%29/builds/27098
>
> BUG=314375
>
> Review URL: https://codereview.chromium.org/47013004

TBR=kbr@chromium.org
BUG=

Review URL: https://codereview.chromium.org/61483002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@233543 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 233543