Fix HeapSnapshotView leaks

Source/devtools/front_end/SplitView.js

 /*
  * 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 24 matching lines @@
  * @param {number=} defaultSidebarWidth
  * @param {number=} defaultSidebarHeight
  */
 WebInspector.SplitView = function(isVertical, secondIsSidebar, settingName, defaultSidebarWidth, defaultSidebarHeight)
 {
     WebInspector.View.call(this);
 
     this.registerRequiredCSS("splitView.css");
     this.element.classList.add("split-view");
 
-    WebInspector.zoomManager.addEventListener(WebInspector.ZoomManager.Events.ZoomChanged, this._onZoomChanged, this);
-
     this._mainView = new WebInspector.VBox();
     this._mainView.makeLayoutBoundary();
     this._mainElement = this._mainView.element;
     this._mainElement.className = "split-view-contents scroll-target split-view-main vbox"; // Override
 
     this._sidebarView = new WebInspector.VBox();
     this._sidebarView.makeLayoutBoundary();
     this._sidebarElement = this._sidebarView.element;
     this._sidebarElement.className = "split-view-contents scroll-target split-view-sidebar vbox"; // Override
 
@@ skipping 508 matching lines @@
 
         var to = totalSize - minMainSize;
         if (from <= to)
             return Number.constrain(sidebarSize, from, to);
 
         return -1;
     },
 
     wasShown: function()
     {
-        this._updateLayout();
+        this._forceUpdateLayout();
+        WebInspector.zoomManager.addEventListener(WebInspector.ZoomManager.Events.ZoomChanged, this._onZoomChanged, this);
+    },
+
+    willHide: function()
+    {
+        WebInspector.zoomManager.removeEventListener(WebInspector.ZoomManager.Events.ZoomChanged, this._onZoomChanged, this);
     },
 
     onResize: function()
     {
         this._updateLayout();
     },
 
     /**
      * @param {!MouseEvent} event
      * @return {boolean}
@@ skipping 186 matching lines @@
         if (this._shouldSaveShowMode)
             orientationState.showMode = this._savedShowMode;
 
         if (this._isVertical)
             state.vertical = orientationState;
         else
             state.horizontal = orientationState;
         setting.set(state);
     },
 
+    _forceUpdateLayout: function()
+    {
+        // Force layout even if sidebar size does not change.
+        this._sidebarSize = -1;
+        this._updateLayout();
+    },
+
     /**
      * @param {!WebInspector.Event} event
      */
     _onZoomChanged: function(event)
     {
-        // Force layout even if sidebar size does not change.
-        this._sidebarSize = -1;
-        if (this.isShowing())
-            this._updateLayout();
+        this._forceUpdateLayout();
     },
 
     /**
      * @param {string} title
      * @param {string} className
      * @return {!WebInspector.StatusBarButton}
      */
     createShowHideSidebarButton: function(title, className)
     {
         console.assert(this.isVertical(), "Buttons for split view with horizontal split are not supported yet.");
@@ skipping 26 matching lines @@
         this._showHideSidebarButton.state = sidebarHidden ? "show" : "hide";
         this._showHideSidebarButton.element.classList.toggle("top-sidebar-show-hide-button", !this.isVertical() && !this.isSidebarSecond());
         this._showHideSidebarButton.element.classList.toggle("right-sidebar-show-hide-button", this.isVertical() && this.isSidebarSecond());
         this._showHideSidebarButton.element.classList.toggle("bottom-sidebar-show-hide-button", !this.isVertical() && this.isSidebarSecond());
         this._showHideSidebarButton.element.classList.toggle("left-sidebar-show-hide-button", this.isVertical() && !this.isSidebarSecond());
         this._showHideSidebarButton.title = sidebarHidden ? WebInspector.UIString("Show %s", this._showHideSidebarButtonTitle) : WebInspector.UIString("Hide %s", this._showHideSidebarButtonTitle);
     },
 
     __proto__: WebInspector.View.prototype
 }