[telemetry] Introduce inject_scripts to replace script_to_evaluate_on_commit.

This CL is to make webdriver-based browser also supports running some javascript before those in the page are run, because the original script_to_evaluate_on_commit is chrome-specific.

BUG=none
TEST=tools/telemetry/run_tests, tools/perf/run_tests --browser=release, tools/perf/run_measurement --browser=release pica, tools/perf/run_measurement --browser=release blink_perf third_party/WebKit/PerformanceTests/, tools/perf/run_multipage_benchmarks --browser=release page_cycler tools/perf/page_sets/page_cycler/moz.json & morejs.json, gpu tests under content/test/gpu/gpu_tests/. No new failures are introduced.

Review URL: https://codereview.chromium.org/23444006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@232099 0039d316-1c4b-4281-b951-d872f2087c98
Roll trace-viewer to r1055

TBR=dsinclair
NOTRY=True

Review URL: https://codereview.chromium.org/54543003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@232100 0039d316-1c4b-4281-b951-d872f2087c98
Update .DEPS.git

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@232101 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 232100
SVN changes up to revision 232101