DevTools: fix disposing of main debugger script mappings

third_party/WebKit/Source/devtools/front_end/bindings/DebuggerWorkspaceBinding.js

Index: third_party/WebKit/Source/devtools/front_end/bindings/DebuggerWorkspaceBinding.js
diff --git a/third_party/WebKit/Source/devtools/front_end/bindings/DebuggerWorkspaceBinding.js b/third_party/WebKit/Source/devtools/front_end/bindings/DebuggerWorkspaceBinding.js
index 78f6ebd7e0c9f633cbd13171b33ed82c6728f53d..256dc7a1e1811371943f940f77c11be7b1119f2f 100644
--- a/third_party/WebKit/Source/devtools/front_end/bindings/DebuggerWorkspaceBinding.js
+++ b/third_party/WebKit/Source/devtools/front_end/bindings/DebuggerWorkspaceBinding.js
@@ -385,8 +385,10 @@ WebInspector.DebuggerWorkspaceBinding.TargetData = function(debuggerModel, debug
     /** @type {!Map.<!WebInspector.UISourceCode, !WebInspector.DebuggerSourceMapping>} */
     this._uiSourceCodeToSourceMapping = new Map();
 
-    debuggerModel.addEventListener(WebInspector.DebuggerModel.Events.ParsedScriptSource, this._parsedScriptSource, this);
-    debuggerModel.addEventListener(WebInspector.DebuggerModel.Events.FailedToParseScriptSource, this._parsedScriptSource, this);
+    this._eventListeners = [
+        debuggerModel.addEventListener(WebInspector.DebuggerModel.Events.ParsedScriptSource, this._parsedScriptSource, this),
+        debuggerModel.addEventListener(WebInspector.DebuggerModel.Events.FailedToParseScriptSource, this._parsedScriptSource, this)
+    ];
 }
 
 WebInspector.DebuggerWorkspaceBinding.TargetData.prototype = {
@@ -453,6 +455,7 @@ WebInspector.DebuggerWorkspaceBinding.TargetData.prototype = {
 
     _dispose: function()
     {
+        WebInspector.EventTarget.removeEventListeners(this._eventListeners);
         this._compilerMapping.dispose();
         this._resourceMapping.dispose();
         this._defaultMapping.dispose();