Added a new pyauto-based flash video performance test to perf.py.

Added a new pyauto-based flash video performance test to perf.py.

This test must be run manually for now, and will be used in its current
state only temporarily to compare results across different ChromeOS
devices.

BUG=None
TEST=Verified the test runs successfully on a local Alex device.

[dennis_jeffrey, 2012-02-01 02:00:53]

Nirnimesh, arscott@ had written a flash test for 1080p video, which we want to
use in the near-term to compare performance across different ChromeOS devices. 
I'm adding a pyauto test to automate execution of this test.

The test is only temporary in its current state, and is not named starting with
"test", so it must be invoked manually.  This test will be revised or removed
later, once we're done using it in its current state.

[Nirnimesh, 2012-02-01 02:04:01]

http://codereview.chromium.org/9320001/diff/1/chrome/test/functional/perf.py
File chrome/test/functional/perf.py (right):

http://codereview.chromium.org/9320001/diff/1/chrome/test/functional/perf.py#...
chrome/test/functional/perf.py:924: webpage_url =
'http://www.corp.google.com/~arscott/fl/FlashVideoTests.html'
It's not a good idea to put internal URLs like this. Please checkin the data
file too

[dennis_jeffrey, 2012-02-01 02:13:31]

http://codereview.chromium.org/9320001/diff/1/chrome/test/functional/perf.py
File chrome/test/functional/perf.py (right):

http://codereview.chromium.org/9320001/diff/1/chrome/test/functional/perf.py#...
chrome/test/functional/perf.py:924: webpage_url =
'http://www.corp.google.com/~arscott/fl/FlashVideoTests.html'
On 2012/02/01 02:04:01, Nirnimesh wrote:
> It's not a good idea to put internal URLs like this. Please checkin the data
> file too

Changed the URL slightly as discussed offline.  It will be a problem checking in
the test completely, since the video file is large (692 MB).  We'll have to
figure that one out if we want the test checked in long-term.

[Nirnimesh, 2012-02-01 02:14:31]

LGTM