Enable VAAPI accelerated decode on Linux

content/content_tests.gypi

 # 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.
 
 {
   'variables': {
     'layouttest_support_content_sources': [
       'public/test/layouttest_support.h',
       'public/test/nested_message_pump_android.cc',
       'public/test/nested_message_pump_android.h',
@@ skipping 1710 matching lines @@
                   '../ui/display/display.gyp:display',  # Used by rendering_helper.cc
                   '../ui/ozone/ozone.gyp:ozone',  # Used by rendering_helper.cc
                 ],
               }],
             ],
             # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
             'msvs_disabled_warnings': [ 4267, ],
           },
         ]
     }],
-    ['chromeos==1 and target_arch != "arm"', {
+    ['(OS=="linux" or chromeos == 1) and target_arch != "arm"', {
       'targets': [
           {
             'target_name': 'vaapi_jpeg_decoder_unittest',
             'type': '<(gtest_target_type)',
             'dependencies': [
               'content.gyp:content_common',
               '../base/base.gyp:base',
               '../media/media.gyp:media',
               '../media/media.gyp:media_test_support',
               '../testing/gtest.gyp:gtest',
@@ skipping 53 matching lines @@
             }],
             ['use_ozone==1', {
               'dependencies': [
                 '../ui/ozone/ozone.gyp:ozone',
               ],
             }],
           ],
         }
       ]
     }],
-    ['chromeos==1', {
+    ['chromeos==1 or OS=="linux"', {
       'targets': [
         {
           'target_name': 'jpeg_decode_accelerator_unittest',
           'type': 'executable',
           'dependencies': [
             '../base/base.gyp:base',
             '../media/media.gyp:media',
             '../media/media.gyp:media_test_support',
             '../testing/gtest.gyp:gtest',
             '../third_party/libyuv/libyuv.gyp:libyuv',
@@ skipping 378 matching lines @@
                   'content_unittests_apk.isolate',
                 ],
               },
             ],
           },
         ],
       ],
     }],
   ],
 }