Core/Movement: Use SetWalk(true/false) instead of AddUnit/RemoveUnit.

src/server/game/AI/SmartScripts/SmartAI.cpp

@@ -45,7 +45,7 @@ SmartAI::SmartAI(Creature* c) : CreatureAI(c)
     mCanRepeatPath = false;
 
     // spawn in run mode
-    me->RemoveUnitMovementFlag(MOVEMENTFLAG_WALKING);
+    me->SetWalk(false);
     mRun = false;
 
     me->GetPosition(&mLastOOCPos);
@@ -720,9 +720,9 @@ uint64 SmartAI::GetGUID(int32 /*id*/)
 void SmartAI::SetRun(bool run)
 {
     if (run)
-        me->RemoveUnitMovementFlag(MOVEMENTFLAG_WALKING);
+        me->SetWalk(false);
     else
-        me->AddUnitMovementFlag(MOVEMENTFLAG_WALKING);
+        me->SetWalk(true);
 
     mRun = run;
 }