[Password Manager] Add UMA stats to track interaction with synced accounts.

components/password_manager/core/browser/password_store_default.h

Index: components/password_manager/core/browser/password_store_default.h
diff --git a/components/password_manager/core/browser/password_store_default.h b/components/password_manager/core/browser/password_store_default.h
index 886a56511998778bcfb740a40204e777eb7abda6..a8038b3e56a741837359c262d7d6ccc0ee529601 100644
--- a/components/password_manager/core/browser/password_store_default.h
+++ b/components/password_manager/core/browser/password_store_default.h
@@ -27,7 +27,8 @@ class PasswordStoreDefault : public PasswordStore {
   virtual ~PasswordStoreDefault();
 
   // Implements PasswordStore interface.
-  virtual void ReportMetricsImpl() OVERRIDE;
+  virtual void ReportMetricsImpl(const std::string& sync_username,
+                                 enum SyncState sync_state) OVERRIDE;
   virtual PasswordStoreChangeList AddLoginImpl(
       const autofill::PasswordForm& form) OVERRIDE;
   virtual PasswordStoreChangeList UpdateLoginImpl(