add target class name to the msg text

Author: rbri

rhino/src/main/java/org/mozilla/javascript/LambdaConstructor.java

@@ -445,7 +445,7 @@ public void setPrototypeScriptable(ScriptableObject proto) {
     @SuppressWarnings("unchecked")
     public static <T> T convertThisObject(Scriptable thisObj, Class<T> targetClass) {
         if (!targetClass.isInstance(thisObj)) {
-            throw ScriptRuntime.typeErrorById("msg.this.not.instance");
+            throw ScriptRuntime.typeErrorById("msg.this.not.instance", targetClass.getSimpleName());
         }
         return (T) thisObj;
     }

rhino/src/main/resources/org/mozilla/javascript/resources/Messages.properties

@@ -988,7 +988,7 @@ msg.constructor.no.function =\
   The constructor for {0} may not be invoked as a function
 
 msg.this.not.instance =\
-  \"this\" is not an instance of the class
+  \"this\" is not an instance of class {0}
 
 # Promises
 msg.function.expected =\