Support variable changing in SDK interface and v8 native

plugins/org.chromium.sdk/src/org/chromium/sdk/internal/v8native/CallFrameImpl.java

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.sdk.internal.v8native;
 
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.atomic.AtomicReference;
@@ skipping 149 matching lines @@
 
     PropertyReference ref = V8Helper.computeReceiverRef(frameObject);
     if (ref == null) {
       result = null;
     } else {
       ValueLoader valueLoader = context.getValueLoader();
       ValueMirror mirror =
           valueLoader.getOrLoadValueFromRefs(Collections.singletonList(ref)).get(0);
       // This name should be string. We are making it string as a fall-back strategy.
       String varNameStr = ref.getName().toString();
-      result = new JsVariableBase.Impl(valueLoader, mirror, varNameStr);
+      // 'this' variable is not mutable. Consider making it mutable.
+      result = new JsVariableBase.Impl(null, valueLoader, mirror, varNameStr);
     }
     if (result != null) {
       receiverVariableRef.compareAndSet(null, result);
     }
   }
 
   @Override
   public TextStreamPosition getStatementStartPosition() {
     return textStreamPosition;
   }
@@ skipping 188 matching lines @@
     }
 
     @Override
     public boolean canRestartFrame(CallFrame callFrame) {
       return callFrame.getScript() != null;
     }
   };
 
   private static final String DEBUGGER_RESERVED = "debugger";
 }