Enable media_perftests on linux perfbot.

testing/buildbot/gn_isolate_map.pyl

 ## Copyright 2015 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.
 
 # gn_isolate_map.pyl - A mapping of Ninja build target names to GN labels and
 # test type classifications for the tests that are run on the bots.
 #
 # This mapping is used by MB so that we can uniformly refer to test binaries
 # by their Ninja target names in the recipes and not need to worry about how
 # they are referred to in GN or GYP specifically (the GYP target name is pretty
@@ skipping 826 matching lines @@
     ],
   },
   "cc_perftests": {
     "label": "//cc:cc_perftests",
     "type": "script",
     "script": "//testing/scripts/run_gtest_perf_test.py",
     "args": [
       "cc_perftests",
     ],
   },
+  "media_perftests": {
+    "label": "//media:media_perftests",
+    "type": "script",
+    "script": "//testing/scripts/run_gtest_perf_test.py",
+    "args": [
+      "media_perftests",
+    ],
+  },
   "load_library_perf_tests": {
     "label": "//chrome/test:load_library_perf_tests",
     "type": "script",
     "script": "//testing/scripts/run_gtest_perf_test.py",
     "args": [
       "load_library_perf_tests",
       "--test-launcher-print-test-stdio=always"
     ],
   },
   "tracing_perftests": {
@@ skipping 124 matching lines @@
   },
   "wm_unittests": {
     "label": "//ui/wm:wm_unittests",
     "type": "windowed_test_launcher",
   },
   "wtf_unittests": {
     "label": "//third_party/WebKit/Source/wtf:wtf_unittests",
     "type": "console_test_launcher",
   },
 }