Drive: add a method to clear all local cache.

chrome/browser/chromeos/extensions/file_browser_event_router.cc

Index: chrome/browser/chromeos/extensions/file_browser_event_router.cc
diff --git a/chrome/browser/chromeos/extensions/file_browser_event_router.cc b/chrome/browser/chromeos/extensions/file_browser_event_router.cc
index ed931c3293be4707094799dfca2cedb6028d8a2a..111e72a2f8dff706272f0d7a6e91e0e1b693d157 100644
--- a/chrome/browser/chromeos/extensions/file_browser_event_router.cc
+++ b/chrome/browser/chromeos/extensions/file_browser_event_router.cc
@@ -321,7 +321,7 @@ void FileBrowserEventRouter::MountCompleted(
           system_service ? system_service->cache() : NULL;
       if (cache) {
         cache->SetMountedStateOnUIThread(
-            source_path, false, gdata::SetMountedStateCallback());
+            source_path, false, gdata::ChangeCacheStateCallback());
       }
     }
   }