Remove all_android.gyp.

It's been unused for two weeks, and should be a noop for everyone who sourced
envsetup since.

If you see an error message like

  gyp: buid/all_android.gyp not found (cwd: /path/to/chrome/src)

after this change, open a fresh shell (and source envsetup),
or run `unset CHROMIUM_GYP_FILE`.

Also remove the code for unsetting CHROMIUM_GYP_FIE from envsetup
and fold the one line left in common_gyp_vars into its only caller.
BUG=330631
R=torne@chromium.org

Review URL: https://codereview.chromium.org/150903005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@248748 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 248748
telemetry: Check compositing features in rasterize and record micro

Instead of disabling the benchmark on Linux, the measurement now checks if
the required compositing features are enabled and exits if they are not.

R=vmpstr@chromium.org
BUG=

Review URL: https://codereview.chromium.org/153083004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@248750 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 248750