[turbolizer] Fix selection bugs and performance problems

tools/turbolizer/turbo-visualizer.js

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 document.onload = (function(d3){
   "use strict";
   var jsonObj;
   var sourceExpandClassList = document.getElementById(SOURCE_EXPAND_ID).classList;
   var sourceCollapseClassList = document.getElementById(SOURCE_COLLAPSE_ID).classList;
   var sourceExpanded = sourceCollapseClassList.contains(COLLAPSE_PANE_BUTTON_VISIBLE);
@@ skipping 150 matching lines @@
         filereader.onload = function(){
           var txtRes = filereader.result;
           // If the JSON isn't properly terminated, assume compiler crashed and
           // add best-guess empty termination
           if (txtRes[txtRes.length-2] == ',') {
             txtRes += '{"name":"disassembly","type":"disassembly","data":""}]}';
           }
           try{
             jsonObj = JSON.parse(txtRes);
 
+            hideCurrentPhase();
+
             sourceView.initializeCode(jsonObj.source, jsonObj.sourcePosition);
             disassemblyView.initializeCode(jsonObj.source, jsonObj.sourcePosition);
             schedule.setNodePositionMap(jsonObj.nodePositions);
 
             var selectMenu = document.getElementById('display-selector');
             var disassemblyPhase = null;
             selectMenu.innerHTML = '';
             for (var i = 0; i < jsonObj.phases.length; ++i) {
               var optionElement = document.createElement("option");
               optionElement.text = jsonObj.phases[i].name;
@@ skipping 65 matching lines @@
   empty = new EmptyView(EMPTY_PANE_ID, selectionBroker);
 
   initializeHandlers(graph);
 
   setSourceExpanded(getLastExpandedState("source", true));
   setDisassemblyExpanded(getLastExpandedState("disassembly", false));
 
   displayPhaseView(empty, null);
   fitPanesToParents();
 })(window.d3);