[Android] Re-enable content_browsertests on main waterfall.

build/android/pylib/gtest/gtest_config.py

 # 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.
 
 """Configuration file for android gtest suites."""
 
 # Add new suites here before upgrading them to the stable list below.
 EXPERIMENTAL_TEST_SUITES = [
-    'content_browsertests',
     'content_gl_tests',
 ]
 
 # Do not modify this list without approval of an android owner.
 # This list determines which suites are run by default, both for local
 # testing and on android trybots running on commit-queue.
 STABLE_TEST_SUITES = [
     'android_webview_unittests',
     'base_unittests',
     'cc_unittests',
     'components_unittests',
     'content_unittests',
     'gl_tests',
     'gpu_unittests',
     'ipc_tests',
     'media_unittests',
     'net_unittests',
     'sql_unittests',
     'sync_unit_tests',
     'ui_unittests',
     'unit_tests',
     'webkit_compositor_bindings_unittests',
     'webkit_unit_tests',
     'breakpad_unittests',
     'sandbox_linux_unittests',
+    'content_browsertests',
 ]
 
 WEBRTC_CHROMIUM_TEST_SUITES = [
     'content_browsertests',
 ]
 
 WEBRTC_NATIVE_TEST_SUITES = [
     'audio_decoder_unittests',
     'common_audio_unittests',
     'common_video_unittests',
     'modules_tests',
     'modules_unittests',
     'neteq_unittests',
     'system_wrappers_unittests',
     'test_support_unittests',
     'tools_unittests',
     'video_engine_core_unittests',
     'voice_engine_unittests',
 ]