Convert aura_unittests to run exclusively on Swarming

ui/aura/aura.gyp

 # Copyright (c) 2012 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': {
     'chromium_code': 1,
   },
   'targets': [
     {
@@ skipping 296 matching lines @@
         }],
         ['OS=="linux" and use_allocator!="none"', {
           'dependencies': [
            # See http://crbug.com/162998#c4 for why this is needed.
             '../../base/allocator/allocator.gyp:allocator',
           ],
         }],
       ],
     },
   ],
+  'conditions': [
+    ['test_isolation_mode != "noop"', {
+      'targets': [
+        {
+          'target_name': 'aura_unittests_run',
+          'type': 'none',
+          'dependencies': [
+            'aura_unittests',
+          ],
+          'includes': [
+            '../../build/isolate.gypi',
+          ],
+          'sources': [
+            'aura_unittests.isolate',
+          ],
+        },
+      ],
+    }],
+  ],
 }