Add isolate for content_browsertests with --site-per-process.

content/content_site_isolation_browsertests.isolate

Index: content/content_site_isolation_browsertests.isolate
diff --git a/google_apis/google_apis_unittests.isolate b/content/content_site_isolation_browsertests.isolate
similarity index 56%
copy from google_apis/google_apis_unittests.isolate
copy to content/content_site_isolation_browsertests.isolate
index 5d9e22e8ba96da5edbf6590fcc064ace809420ad..9fcfd9ac72807d74f7b5e9470141957752e98644 100644
--- a/google_apis/google_apis_unittests.isolate
+++ b/content/content_site_isolation_browsertests.isolate
@@ -3,20 +3,17 @@
 # found in the LICENSE file.
 {
   'includes': [
-    '../base/base.isolate',
+    'content_browsertests.isolate',
   ],
   'conditions': [
-    ['OS=="win" or OS=="mac" or OS=="linux"', {
+    ['OS=="linux"', {
       'variables': {
         'command': [
           '../testing/test_env.py',
-          '<(PRODUCT_DIR)/google_apis_unittests<(EXECUTABLE_SUFFIX)',
-          '--brave-new-test-launcher',
+          '<(PRODUCT_DIR)/content_browsertests<(EXECUTABLE_SUFFIX)',
           '--test-launcher-bot-mode',
-        ],
-        'files': [
-          '../testing/test_env.py',
-          'test/',
+					'--site-per-process',
+					'--test-launcher-filter-file=../testing/buildbot/filters/site-per-process.content_browsertests.filter',
         ],
       },
     }],