content_browsertests.isolate: ppapi_tests requires enable_plugins=1.

content/content_browsertests.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.
 {
   'conditions': [
     ['use_x11==0', {
       'variables': {
         'command': [
           '../testing/test_env.py',
           '<(PRODUCT_DIR)/content_browsertests<(EXECUTABLE_SUFFIX)',
@@ skipping 50 matching lines @@
           'test/data/',
         ],
       },
     }],
     ['OS=="linux"', {
       'variables': {
         'files': [
           '<(PRODUCT_DIR)/content_shell.pak',
           '<(PRODUCT_DIR)/libffmpegsumo.so',
           '<(PRODUCT_DIR)/libosmesa.so',
+        ],
+      },
+    }],
+    ['OS=="linux" and enable_plugins==1', {
+      'variables': {
+        'files': [
           '<(PRODUCT_DIR)/libppapi_tests.so',
         ],
       },
     }],
     ['OS=="linux" or OS=="mac" or OS=="win"', {
       'variables': {
         'files': [
           '../net/tools/testserver/',
           '../ppapi/tests/test_case.html',
           '../ppapi/tests/test_page.css',
@@ skipping 56 matching lines @@
         ],
       },
     }],
   ],
   'includes': [
     '../base/base.isolate',
     '../gin/v8.isolate',
     '../third_party/angle/angle.isolate',
   ],
 }