[Telemetry] Make record_wpr call test.WillNavigateToPage and test.DidNavigateToPage.

Make record_wpr call test.WillNavigateToPage and test.DidNavigateToPage.

BUG=331607
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=245333

[slamm, 2014-01-14 23:29:26]

I needed these changes to record my new measurement.
I am unsure if there would be a better way to forward calls to all the
overridable test methods.

[tonyg, 2014-01-15 00:46:58]

lgtm

[commit-bot: I haz the power, 2014-01-16 14:37:27]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/slamm@chromium.org/138643002/1

[commit-bot: I haz the power, 2014-01-16 19:36:42]

Retried try job too often on win_rel for step(s) app_list_unittests,
ash_unittests, aura_unittests, cacheinvalidation_unittests, cc_unittests,
check_deps, check_deps2git, chrome_elf_unittests, chromedriver_unittests,
components_unittests, compositor_unittests, content_browsertests,
content_unittests, crypto_unittests, events_unittests, google_apis_unittests,
gpu_unittests, installer_util_unittests, ipc_tests, jingle_unittests,
media_unittests, mini_installer_test, nacl_integration, ppapi_unittests,
printing_unittests, remoting_unittests, sql_unittests, sync_integration_tests,
sync_unit_tests, telemetry_unittests, views_unittests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...

[commit-bot: I haz the power, 2014-01-16 19:57:09]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/slamm@chromium.org/138643002/1

[commit-bot: I haz the power, 2014-01-16 21:38:45]

Change committed as 245333