[Sync] - Upload the callstacks for errors so that the line number of error is in callstack.

chrome/browser/sync/glue/model_associator.h

Index: chrome/browser/sync/glue/model_associator.h
diff --git a/chrome/browser/sync/glue/model_associator.h b/chrome/browser/sync/glue/model_associator.h
index 891f3ffd9515e1f546e7306a66f7f7d6e1f0d9d5..da10d03f03c83a9d7ad4f32f9b4348ffc8149d97 100644
--- a/chrome/browser/sync/glue/model_associator.h
+++ b/chrome/browser/sync/glue/model_associator.h
@@ -30,12 +30,10 @@ class AssociatorInterface {
   // should be identical and corresponding. Returns true on
   // success. On failure of this step, we should abort the sync
   // operation and report an error to the user.
-  // TODO(zea): return a SyncError instead of passing one in.
-  virtual bool AssociateModels(SyncError* error) = 0;
+  virtual SyncError AssociateModels() = 0;
 
   // Clears all the associations between the chrome and sync models.
-  // TODO(zea): return a SyncError instead of passing one in.
-  virtual bool DisassociateModels(SyncError* error) = 0;
+  virtual SyncError DisassociateModels() = 0;
 
   // The has_nodes out parameter is set to true if the sync model has
   // nodes other than the permanent tagged nodes.  The method may