Reflect new naming of isolate files for android_webview_test.

scripts/slave/recipe_modules/chromium_android/example.expected/perf_tests_failure.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "\nimport os, sys\n\nbuild_path = sys.argv[1]\nif os.path.exists(build_path):\n  for (path, dir, files) in os.walk(build_path):\n    for cur_file in files:\n      if cur_file.endswith('index.lock'):\n        path_to_file = os.path.join(path, cur_file)\n        print 'deleting %s' % path_to_file\n        os.remove(path_to_file)\n",
       "[SLAVE_BUILD]"
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "cleanup index.lock",
@@ skipping 725 matching lines @@
       "--screenshot",
       "--host-driven-root",
       "[SLAVE_BUILD]/src/chrome/test",
       "--test-apk",
       "[SLAVE_BUILD]/src/out/Release/apks/AndroidWebViewTest.apk",
       "--apk-under-test",
       "[SLAVE_BUILD]/src/out/Release/apks/AndroidWebView.apk",
       "--additional-apk",
       "Additional.apk",
       "--isolate-file-path",
-      "android_webview/android_webview_test_apk.isolate",
+      "android_webview/android_webview_test_data.isolate",
       "--release",
       "--official-build"
     ],
     "cwd": "[SLAVE_BUILD]",
     "env": {
       "CHROMIUM_OUTPUT_DIR": "[SLAVE_BUILD]/src/out/Release"
     },
     "name": "Instrumentation test SmallTest"
   },
   {
@@ skipping 72 matching lines @@
       "PATH": "[SLAVE_BUILD]/src/third_party/android_tools/sdk/platform-tools:[SLAVE_BUILD]/src/build/android:%(PATH)s"
     },
     "name": "stack_tool_for_asan"
   },
   {
     "name": "$result",
     "reason": "sharded perf tests failed [StepFailure(\"Step('perf_test.foo') failed with return_code 1\",)]",
     "status_code": 1
   }
 ]