Fixes to make GPU tests run in isolated mode.

chrome/telemetry_gpu_test.isolate

 # Copyright (c) 2013 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.
 {
   'includes': [
     'telemetry.isolate',
   ],
   'conditions': [
     ['OS=="android" or OS=="linux" or OS=="mac" or OS=="win"', {
       # This isolate allows any of the GPU tests, including the WebGL
       # conformance tests, to be run. However, extra command line arguments
       # must be supplied in order to run any one of them.
       'variables': {
         'isolate_dependency_untracked': [
           '../content/test/gpu/',
           '../content/test/data/gpu/',
           # For GpuProcess.video
           '../content/test/data/media/bear.ogv',
           # For webgl_conformance
           '../third_party/webgl/',
         ],
         'command': [
-          '../content/test/gpu/run_gpu_test',
+          '../content/test/gpu/run_gpu_test.py',
         ],
       },
     }],
   ]
 }