Added Tab.SnapshotContent and MapsGL example to telemetry

tools/telemetry/telemetry/tab_test_case.py

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 import unittest
 
 from telemetry import browser_finder
 from telemetry import options_for_unittests
 
 class TabTestCase(unittest.TestCase):
   def setUp(self):
     self._browser = None
     self._tab = None
     options = options_for_unittests.Get()
+    options.extra_browser_args.append('--enable-gpu-benchmarking')

[nduca, 2012/11/12 19:53:26]

dont love this.... can you make the specific screenshot test do this instead of
all tests?

     browser_to_create = browser_finder.FindBrowser(options)
     if not browser_to_create:
       raise Exception('No browser found, cannot continue test.')
     try:
       self._browser = browser_to_create.Create()
       self._tab = self._browser.ConnectToNthTab(0)
     except:
       self.tearDown()
       raise
 
   def tearDown(self):
     if self._tab:
       self._tab.Close()
     if self._browser:
       self._browser.Close()