harmony-scoping: Implement debugger support for script scope.

src/mirror-debugger.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.
 
 // Handle id counters.
 var next_handle_ = 0;
 var next_transient_handle_ = -1;
 
 // Mirror cache.
 var mirror_cache_ = [];
@@ skipping 175 matching lines @@
 
 
 // Different attributes for a property.
 var PropertyAttribute = {};
 PropertyAttribute.None       = NONE;
 PropertyAttribute.ReadOnly   = READ_ONLY;
 PropertyAttribute.DontEnum   = DONT_ENUM;
 PropertyAttribute.DontDelete = DONT_DELETE;
 
 
-// A copy of the scope types from runtime.cc.
+// A copy of the scope types from runtime-debug.cc.
+// NOTE: these constants should be backward-compatible, so
+// add new ones to the end of this list.
 var ScopeType = { Global: 0,
                   Local: 1,
                   With: 2,
                   Closure: 3,
                   Catch: 4,
-                  Block: 5 };
+                  Block: 5,
+                  Script: 6 };
 
 
 // Mirror hierarchy:
 //   - Mirror
 //     - ValueMirror
 //       - UndefinedMirror
 //       - NullMirror
 //       - NumberMirror
 //       - StringMirror
 //       - SymbolMirror
@@ skipping 2073 matching lines @@
   return this.scope_index_;
 };
 
 
 ScopeMirror.prototype.scopeType = function() {
   return this.details_.type();
 };
 
 
 ScopeMirror.prototype.scopeObject = function() {
-  // For local and closure scopes create a transient mirror as these objects are
-  // created on the fly materializing the local or closure scopes and
-  // therefore will not preserve identity.
+  // For local, closure and script scopes create a transient mirror
+  // as these objects are created on the fly materializing the local
+  // or closure scopes and therefore will not preserve identity.
   var transient = this.scopeType() == ScopeType.Local ||
-                  this.scopeType() == ScopeType.Closure;
+                  this.scopeType() == ScopeType.Closure ||
+                  this.scopeType() == ScopeType.Script;
   return MakeMirror(this.details_.object(), transient);
 };
 
 
 ScopeMirror.prototype.setVariableValue = function(name, new_value) {
   this.details_.setVariableValueImpl(name, new_value);
 };
 
 
 /**
@@ skipping 703 matching lines @@
   }
   if (!NUMBER_IS_FINITE(value)) {
     if (value > 0) {
       return 'Infinity';
     } else {
       return '-Infinity';
     }
   }
   return value;
 }