[WIP] DevTools: user SourceMapManager in Debugger

third_party/WebKit/Source/devtools/front_end/platform/utilities.js

 /*
  * Copyright (C) 2007 Apple Inc.  All rights reserved.
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 1195 matching lines @@
   /**
    * @return {number}
    */
   get size() {
     return this._map.size;
   },
 
   /**
    * @param {K} key
    * @param {V} value
+   * @return {boolean}
    */
   remove: function(key, value) {
     var values = this.get(key);
-    values.delete(value);
+    var result = values.delete(value);
     if (!values.size)
       this._map.delete(key);
+    return result;
   },
 
   /**
    * @param {K} key
    */
   removeAll: function(key) {
     this._map.delete(key);
   },
 
   /**
@@ skipping 203 matching lines @@
   function windowLoaded() {
     self.removeEventListener('DOMContentLoaded', windowLoaded, false);
     callback();
   }
 
   if (document.readyState === 'complete' || document.readyState === 'interactive')
     callback();
   else
     self.addEventListener('DOMContentLoaded', windowLoaded, false);
 }