docs($location): clarify the two-way data-binding note

Closes angular#1030

Author: IgorMinar

docs/content/guide/dev_guide.services.$location.ngdoc

@@ -611,8 +611,11 @@ then uses the information it obtains to compose hashbang URLs (such as
 ## Two-way binding to $location
 
 The Angular's compiler currently does not support two-way binding for methods (see {@link
-https://github.com/angular/angular.js/issues/404 issue}).  If you should require two-way binding,
-you will need to specify an extra property that has two watchers. For example:
+https://github.com/angular/angular.js/issues/404 issue}).  If you should require two-way binding
+to the $location object (using {@link api/angular.module.ng.$compileProvider.directive.input.text
+ngModel} directive on an input field), you will need to specify an extra model property
+(e.g. `locationPath`) with two watchers which push $location updates in both directions. For
+example:
 <pre>
 <!-- html -->
 <input type="text" ng-model="locationPath" />