Move mock_special_storage_policy from webkit/ to content/public/test/

content/content_tests.gypi

Index: content/content_tests.gypi
diff --git a/content/content_tests.gypi b/content/content_tests.gypi
index 602a964d21bd43ee3b7d921e742606c57a60fb0a..2be811c14e9b0dd4deef3fb7e2240682727a2ab9 100644
--- a/content/content_tests.gypi
+++ b/content/content_tests.gypi
@@ -342,8 +342,8 @@
         '../webkit/common/webkit_common.gyp:webkit_common',
       ],
       'sources': [
-        '../webkit/browser/quota/mock_special_storage_policy.cc',
-        '../webkit/browser/quota/mock_special_storage_policy.h',
+        'public/test/mock_special_storage_policy.cc',
+        'public/test/mock_special_storage_policy.h',
       ],
     },
     {
@@ -405,6 +405,7 @@
         'browser/child_process_security_policy_unittest.cc',
         'browser/compositor/software_browser_compositor_output_surface_unittest.cc',
         'browser/compositor/software_output_device_ozone_unittest.cc',
+        'browser/database_tracker_unittest.cc',
         'browser/device_sensors/data_fetcher_shared_memory_base_unittest.cc',
         'browser/device_sensors/sensor_manager_android_unittest.cc',
         'browser/devtools/devtools_http_handler_unittest.cc',
@@ -672,7 +673,6 @@
         'test/run_all_unittests.cc',
         '../webkit/browser/blob/local_file_stream_reader_unittest.cc',
         '../webkit/browser/database/database_quota_client_unittest.cc',
-        '../webkit/browser/database/database_tracker_unittest.cc',
         '../webkit/browser/database/database_util_unittest.cc',
         '../webkit/browser/database/databases_table_unittest.cc',
         '../webkit/browser/fileapi/external_mount_points_unittest.cc',