Add PPAPI test mock headers to *.isolate files.

chrome/browser_tests.isolate

 # 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.
 {
   'conditions': [
     ['use_x11==0', {
       'variables': {
         'command': [
           '../testing/test_env.py',
           '<(PRODUCT_DIR)/browser_tests<(EXECUTABLE_SUFFIX)',
@@ skipping 49 matching lines @@
     ['OS=="linux" or OS=="mac" or OS=="win"', {
       'variables': {
         'files': [
           '../content/test/data/',
           '../google_apis/test/',
           '../media/test/data/',
           '../media/test/data/',
           '../net/data/',
           '../net/tools/testserver/',
           '../ppapi/tests/test_case.html',
+          '../ppapi/tests/test_case.html.mock-http-headers',
           '../ppapi/tests/test_page.css',
+          '../ppapi/tests/test_page.css.mock-http-headers',
           '../testing/test_env.py',
           '../third_party/accessibility-audit/axs_testing.js',
           '../third_party/pyftpdlib/',
           '../third_party/pywebsocket/',
           '../third_party/safe_browsing/',
           '../third_party/simplejson/',
           '../third_party/tlslite/',
           '<(PRODUCT_DIR)/browser_tests<(EXECUTABLE_SUFFIX)',
           '<(PRODUCT_DIR)/browser_tests.pak',
           '<(PRODUCT_DIR)/peerconnection_server<(EXECUTABLE_SUFFIX)',
           '<(PRODUCT_DIR)/pseudo_locales/',
           '<(PRODUCT_DIR)/pyproto/',
           # TODO(jam): above is directory for GYP. GN uses:
           #'<(SHARED_INTERMEDIATE_DIR)/google/',
           #'<(SHARED_INTERMEDIATE_DIR)/policy/proto/',
           '<(PRODUCT_DIR)/remoting/unittests/',
           '<(PRODUCT_DIR)/test_case.html',
           '<(PRODUCT_DIR)/test_case.html.mock-http-headers',
           '<(PRODUCT_DIR)/test_data/',
           '<(PRODUCT_DIR)/test_page.css',
+          '<(PRODUCT_DIR)/test_page.css.mock-http-headers',
           '<(PRODUCT_DIR)/test_url_loader_data/',
           'browser/policy/test/asn1der.py',
           'browser/policy/test/policy_testserver.py',
           'common/extensions/docs/examples/apps/calculator/',
           'test/data/',
           'third_party/mock4js/',
         ],
         'read_only': 1,
       },
     }],
@@ skipping 160 matching lines @@
           'browser/chromeos/login/test/https_forwarder.py',
         ],
       },
     }],
   ],
   'includes': [
     '../base/base.isolate',
     'chrome.isolate',
   ],
 }