Adding URLResponse Disk Cache to mojo.

mojo/tools/data/apptests

 # This file contains a list of Mojo gtest unit tests.
 #
 # This must be valid Python. It may use the |config| global that will be a
 # mopy.config.Config object, and must set a |tests| global that will contain the
 # list of tests to run.
 #
 # The entries in |tests| are dictionaries of the following form:
 #   {
 #     # Required URL for apptest.
 #     "test": "mojo:test_app_url",
@@ skipping 103 matching lines @@
     {
       "test": "mojo:dart_apptests",
       "type": "dart",
     },
     {
       # https://github.com/domokit/mojo/issues/61
       # Sometime the shell get a trucated application when exposed through the
       # http server.
       "test": "mojo:shell_apptests",
     },
+    {
+      "test": "mojo:url_response_disk_cache_apptests",
+    },
   ]