[builtins] Drop useless ToBoolean JavaScript builtin.

src/debug/mirrors.js

 // Copyright 2006-2012 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.
 
 (function(global, utils) {
 "use strict";
 
 // ----------------------------------------------------------------------------
 // Imports
 
 var FunctionSourceString;
 var GlobalArray = global.Array;
 var IsNaN = global.isNaN;
 var JSONStringify = global.JSON.stringify;
 var MathMin = global.Math.min;
 var promiseStatusSymbol = utils.ImportNow("promise_status_symbol");
 var promiseValueSymbol = utils.ImportNow("promise_value_symbol");
 var SymbolToString;
-var ToBoolean;
 
 utils.Import(function(from) {
   FunctionSourceString = from.FunctionSourceString;
   SymbolToString = from.SymbolToString;
-  ToBoolean = from.ToBoolean;
 });
 
 // ----------------------------------------------------------------------------
 
 // Mirror hierarchy:
 // - Mirror
 //   - ValueMirror
 //     - UndefinedMirror
 //     - NullMirror
 //     - BooleanMirror
@@ skipping 2030 matching lines @@
   return result;
 };
 
 
 FrameMirror.prototype.evaluate = function(source, disable_break,
                                           opt_context_object) {
   return MakeMirror(%DebugEvaluate(this.break_id_,
                                    this.details_.frameId(),
                                    this.details_.inlinedFrameIndex(),
                                    source,
-                                   ToBoolean(disable_break),
+                                   TO_BOOLEAN(disable_break),
                                    opt_context_object));
 };
 
 
 FrameMirror.prototype.invocationText = function() {
   // Format frame invoaction (receiver, function and arguments).
   var result = '';
   var func = this.func();
   var receiver = this.receiver();
   if (this.isConstructCall()) {
@@ skipping 1026 matching lines @@
 // Functions needed by the debugger runtime.
 utils.InstallFunctions(utils, DONT_ENUM, [
   "ClearMirrorCache", ClearMirrorCache
 ]);
 
 // Export to debug.js
 utils.Export(function(to) {
   to.MirrorType = MirrorType;
 });
 })