Make profiling lock global rather than per Target

Source/devtools/front_end/sdk/TimelineManager.js

 /*
  * Copyright (C) 2011 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 51 matching lines @@
     /**
      * @param {number=} maxCallStackDepth
      * @param {string=} liveEvents
      * @param {boolean=} includeCounters
      * @param {boolean=} includeGPUEvents
      * @param {function(?Protocol.Error)=} callback
      */
     start: function(maxCallStackDepth, liveEvents, includeCounters, includeGPUEvents, callback)
     {
         this._enablementCount++;
-        this.target().profilingLock.acquire();
+        WebInspector.profilingLock.acquire();
         if (WebInspector.experimentsSettings.timelineJSCPUProfile.isEnabled() && maxCallStackDepth) {
             this._configureCpuProfilerSamplingInterval();
             this._jsProfilerStarted = true;
             this.target().profilerAgent().start();
         }
         if (this._enablementCount === 1)
             this.target().timelineAgent().start(maxCallStackDepth, true, liveEvents, includeCounters, includeGPUEvents, callback);
         else if (callback)
             callback(null);
     },
@@ skipping 13 matching lines @@
         var masterProfile = null;
         var callbackBarrier = new CallbackBarrier();
 
         if (this._jsProfilerStarted) {
             this.target().profilerAgent().stop(callbackBarrier.createCallback(profilerCallback));
             this._jsProfilerStarted = false;
         }
         if (!this._enablementCount)
             this.target().timelineAgent().stop(callbackBarrier.createCallback(timelineCallback));
 
-        callbackBarrier.callWhenDone(allDoneCallback.bind(this));
+        callbackBarrier.callWhenDone(allDoneCallback);
 
         /**
          * @param {?Protocol.Error} error
          */
         function timelineCallback(error)
         {
             masterError = masterError || error;
         }
 
         /**
          * @param {?Protocol.Error} error
          * @param {!ProfilerAgent.CPUProfile} profile
          */
         function profilerCallback(error, profile)
         {
             masterError = masterError || error;
             masterProfile = profile;
         }
 
-        /**
-         * @this {WebInspector.TimelineManager}
-         */
         function allDoneCallback()
         {
-            this.target().profilingLock.release();
+            WebInspector.profilingLock.release();
             callback(masterError, masterProfile);
         }
     },
 
     /**
      * @param {boolean=} consoleTimeline
      * @param {!Array.<!TimelineAgent.TimelineEvent>=} events
      */
     _stopped: function(consoleTimeline, events)
     {
@@ skipping 71 matching lines @@
     },
 
     /**
      * @param {number} count
      */
     progress: function(count)
     {
         this._manager.dispatchEventToListeners(WebInspector.TimelineManager.EventTypes.TimelineProgress, count);
     }
 }