Browsing Data Deletion: Style fixes

chrome/browser/browsing_data/browsing_data_service_worker_helper.h

Index: chrome/browser/browsing_data/browsing_data_service_worker_helper.h
diff --git a/chrome/browser/browsing_data/browsing_data_service_worker_helper.h b/chrome/browser/browsing_data/browsing_data_service_worker_helper.h
index dc9cc9cdc6061a42302859fa940e272ced771f2d..47197794e1d69bc350ed90bc0bcac96ace330f50 100644
--- a/chrome/browser/browsing_data/browsing_data_service_worker_helper.h
+++ b/chrome/browser/browsing_data/browsing_data_service_worker_helper.h
@@ -8,6 +8,7 @@
 #include <list>
 #include <set>
 #include <string>
+#include <vector>
 
 #include "base/callback.h"
 #include "base/compiler_specific.h"
@@ -63,7 +64,7 @@ class BrowsingDataServiceWorkerHelper
   // Indicates whether or not we're currently fetching information:
   // it's true when StartFetching() is called in the UI thread, and it's reset
   // after we notified the callback in the UI thread.
-  // This only mutates on the UI thread.
+  // This member is only mutated on the UI thread.
   bool is_fetching_;
 
  private: