adb_profile_chrome: Add perf profiler

adb_profile_chrome: Add perf profiler

This patch makes it possible to run the perf profiler
through adb_profile_chrome. The result is a trace file that
contains samples from perf as well as events from Chrome
trace events or systrace.

For example, to find out in which functions CPU time is
being spent:

$ build/android/adb_profile_chrome --browser build --time 5 --perf

BUG=375754
TEST=build/android/chrome_profiler/run_tests
NOTRY=true

Review URL: https://codereview.chromium.org/293193002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@274837 0039d316-1c4b-4281-b951-d872f2087c98