Increase possible number of frames on the wire.

Previous thresholds were defined assuming low values for
|rtp_max_delay_ms| (in audio and video receiver configurations).

Review URL: https://codereview.chromium.org/196513003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@256859 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 256859
Cleanup: Remove declaration of never-defined, never-called function ChromeResourceDispatcherHostDelegate::AppendChromeMetricsHeaders.

This function isn't defined anywhere, and confused me a bit when I saw
it in the header.

Review URL: https://codereview.chromium.org/189373007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@256861 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 256861