Prepare for -Wall for third-party code, -Wextra for chromium_code

chrome/browser/chromeos/file_system_provider/service_unittest.cc

Index: chrome/browser/chromeos/file_system_provider/service_unittest.cc
diff --git a/chrome/browser/chromeos/file_system_provider/service_unittest.cc b/chrome/browser/chromeos/file_system_provider/service_unittest.cc
index 0d5ea1e5c75ed65d4e26968d3ab39d078d2e6c72..8dea0815f390a97486928be26f484ca934be909f 100644
--- a/chrome/browser/chromeos/file_system_provider/service_unittest.cc
+++ b/chrome/browser/chromeos/file_system_provider/service_unittest.cc
@@ -151,10 +151,10 @@ class FakeRegistry : public RegistryInterface {
     it->second.last_tag = watcher.last_tag;
   }
 
-  ProvidedFileSystemInfo* const file_system_info() const {
+  const ProvidedFileSystemInfo* file_system_info() const {
     return file_system_info_.get();
   }
-  Watchers* const watchers() const { return watchers_.get(); }
+  const Watchers* watchers() const { return watchers_.get(); }
 
  private:
   scoped_ptr<ProvidedFileSystemInfo> file_system_info_;