Preliminary code for block scopes and block contexts.

src/d8.js

 // Copyright 2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 85 matching lines @@
 Debug.ScriptCompilationType = { Host: 0,
                                 Eval: 1,
                                 JSON: 2 };
 
 
 // The different types of scopes matching constants runtime.cc.
 Debug.ScopeType = { Global: 0,
                     Local: 1,
                     With: 2,
                     Closure: 3,
-                    Catch: 4 };
+                    Catch: 4,
+                    Block: 5 };
 
 
 // Current debug state.
 const kNoFrame = -1;
 Debug.State = {
   currentFrame: kNoFrame,
   displaySourceStartLine: -1,
   displaySourceEndLine: -1,
   currentSourceLine: -1
 }
@@ skipping 2680 matching lines @@
       json += NumberToJSON_(elem);
     } else if (typeof(elem) === 'string')  {
       json += StringToJSON_(elem);
     } else {
       json += elem;
     }
   }
   json += ']';
   return json;
 }