Check lock type

[andrecostea]

Need to collect the type of the lock, otherwise we might end up creating locks on non-reference types leading to a type error in Java.

For:

       protected void haha(int x){    
       //    synchronized(myA2){
               myA.f = x;
       //    }
       }  

we currently generate:

        protected void haha(int x){     
        //    synchronized(myA2){ 
                synchronized(myA.f) {myA.f = x;} 
         
        //    } 
        }  

when we actually should generate:
we currently generate:

        protected void haha(int x){     
        //    synchronized(myA2){ 
                synchronized(myA) {myA.f = x;} 
         
        //    } 
        }