Coverity: Pass parameters by reference.

chrome/browser/sync/glue/autofill_model_associator2.h

Index: chrome/browser/sync/glue/autofill_model_associator2.h
diff --git a/chrome/browser/sync/glue/autofill_model_associator2.h b/chrome/browser/sync/glue/autofill_model_associator2.h
index 0ad37deb5402f283c7cddb9309e26c015b863200..2b5031063a2f4bd70ed08b42b8655f97a739921a 100644
--- a/chrome/browser/sync/glue/autofill_model_associator2.h
+++ b/chrome/browser/sync/glue/autofill_model_associator2.h
@@ -81,12 +81,12 @@ class AutofillModelAssociator2
   virtual const std::string* GetChromeNodeFromSyncId(int64 sync_id);
 
   // Not implemented.
-  virtual bool InitSyncNodeFromChromeId(std::string node_id,
+  virtual bool InitSyncNodeFromChromeId(const std::string& node_id,
                                         sync_api::BaseNode* sync_node);
 
   // Returns the sync id for the given autofill name, or sync_api::kInvalidId
   // if the autofill name is not associated to any sync id.
-  virtual int64 GetSyncIdFromChromeId(std::string node_id);
+  virtual int64 GetSyncIdFromChromeId(const std::string& node_id);
 
   // Associates the given autofill name with the given sync id.
   virtual void Associate(const std::string* node, int64 sync_id);