DevTools: carefully cleanup CSS sourcemaps

third_party/WebKit/Source/devtools/front_end/sdk/SourceMapManager.js

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @template T
  */
 SDK.SourceMapManager = class extends SDK.SDKObject {
   /**
    * @param {!SDK.Target} target
@@ skipping 166 matching lines @@
         attach.call(this, sourceMapURL, client);
     }
 
     /**
      * @param {string} sourceMapURL
      * @param {!T} client
      * @this {SDK.SourceMapManager}
      */
     function attach(sourceMapURL, client) {
       this._sourceMapURLToClients.set(sourceMapURL, client);
       this.dispatchEventToListeners(SDK.SourceMapManager.Events.SourceMapAttached, client);

[dgozman, 2017/03/28 23:37:37]

Let's pass sourceMap here as well for uniformity.

[lushnikov, 2017/03/29 01:27:24]

Done.

     }
   }
 
   /**
    * @param {!SDK.SourceMap} sourceMap
    * @return {?Runtime.Extension}
    */
   _factoryForSourceMap(sourceMap) {
     var sourceExtensions = new Set();
     for (var url of sourceMap.sourceURLs())
@@ skipping 15 matching lines @@
     this._relativeSourceMapURL.delete(client);
     this._resolvedSourceMapURL.delete(client);
 
     if (!sourceMapURL)
       return;
     if (!this._sourceMapURLToClients.hasValue(sourceMapURL, client)) {
       this._sourceMapURLToLoadingClients.remove(sourceMapURL, client);
       return;
     }
     this._sourceMapURLToClients.remove(sourceMapURL, client);
+    var sourceMap = this._sourceMapByURL.get(sourceMapURL);
     if (!this._sourceMapURLToClients.has(sourceMapURL))
       this._sourceMapByURL.delete(sourceMapURL);
-    this.dispatchEventToListeners(SDK.SourceMapManager.Events.SourceMapDetached, client);
+    this.dispatchEventToListeners(SDK.SourceMapManager.Events.SourceMapDetached, {client, sourceMap});

[lushnikov, 2017/03/28 01:39:32]

used "shorthand property names" here :)

[dgozman, 2017/03/28 23:37:37]

Scary! Maybe trial this feature in tests first?

[lushnikov, 2017/03/29 01:27:24]

Done.

   }
 
   _sourceMapLoadedForTest() {
   }
 
   dispose() {
     SDK.targetManager.removeEventListener(
         SDK.TargetManager.Events.InspectedURLChanged, this._inspectedURLChanged, this);
   }
 };
 
 SDK.SourceMapManager.Events = {
   SourceMapAttached: Symbol('SourceMapAttached'),
   SourceMapDetached: Symbol('SourceMapDetached'),
   SourceMapChanged: Symbol('SourceMapChanged')
 };