Add the ability to clear the shader disk cache.

content/content_tests.gypi

Index: content/content_tests.gypi
diff --git a/content/content_tests.gypi b/content/content_tests.gypi
index e3c4606ae40c75af5cbf8cf5f8ad7f19a7912bfb..23aa4008f1f4ee89edd7a85d7a7f6d0aa138a78c 100644
--- a/content/content_tests.gypi
+++ b/content/content_tests.gypi
@@ -300,6 +300,7 @@
         'browser/gpu/gpu_driver_bug_list_unittest.cc',
         'browser/gpu/gpu_switching_list_unittest.cc',
         'browser/gpu/gpu_util_unittest.cc',
+        'browser/gpu/shader_disk_cache_unittest.cc',
         'browser/host_zoom_map_impl_unittest.cc',
         'browser/hyphenator/hyphenator_message_filter_unittest.cc',
         'browser/in_process_webkit/webkit_thread_unittest.cc',
@@ -348,6 +349,7 @@
         'browser/speech/google_streaming_remote_engine_unittest.cc',
         'browser/speech/speech_recognizer_unittest.cc',
         'browser/ssl/ssl_host_state_unittest.cc',
+        'browser/storage_partition_impl_unittest.cc',
         'browser/storage_partition_impl_map_unittest.cc',
         'browser/streams/stream_unittest.cc',
         'browser/streams/stream_url_request_job_unittest.cc',