docs($rootScope): clean up inheritance example

Closes #10441

src/ng/rootScope.js

@@ -105,7 +105,6 @@ function $RootScopeProvider() {
          var child = parent.$new();
 
          parent.salutation = "Hello";
-         child.name = "World";
          expect(child.salutation).toEqual('Hello');
 
          child.salutation = "Welcome";