Revert of [debugger] debug-evaluate should not not modify local values.

test/mjsunit/debug-evaluate-const.js

 // Copyright 2013 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
 //       with the distribution.
 //     * Neither the name of Google Inc. nor the names of its
 //       contributors may be used to endorse or promote products derived
 //       from this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// Flags: --expose-debug-as debug --debug-eval-readonly-locals
+// Flags: --expose-debug-as debug
 
 Debug = debug.Debug
 
 listenerComplete = false;
 exception = false;
 
 // var0:   init after break point, changed by debug eval.
 // const0: init before break point, changed by debug eval.
 // const1: init after break point, materialized but untouched by debug eval.
 // const2: init after break point, materialized and changed by debug eval.
 // const3: context allocated const, init before break point, changed by eval.
 function f() {
   var var1 = 21;
   const const3 = 3;
 
   function g() {
     const const0 = 0;
     assertEquals(undefined, const1);
     assertEquals(undefined, const2);
     assertEquals(3, const3);
     assertEquals(21, var1);
 
     debugger;  // Break point.
 
-    assertEquals(undefined, var0);
-    assertEquals(0, const0);
+    assertEquals(30, var0);
+    // TODO(yangguo): debug evaluate should not be able to alter
+    //                stack-allocated const values
+    // assertEquals(0, const0);
     assertEquals(undefined, const1);
     assertEquals(undefined, const2);
     var var0 = 20;
     const const1 = 1;
     const const2 = 2;
     assertEquals(20, var0);
     assertEquals(1, const1);
     assertEquals(2, const2);
   }
 
   g();
 
-  assertEquals(21, var1);
+  assertEquals(31, var1);
   assertEquals(3, const3);
 }
 
 
 function listener(event, exec_state, event_data, data) {
   if (event != Debug.DebugEvent.Break) return;
   try {
     var frame = exec_state.frame(0);
     var evaluate = function(something) {
       return frame.evaluate(something).value()
@@ skipping 31 matching lines @@
 try { f(); } catch (e) { }
 
 Debug.setListener(listener);
 
 f();
 
 Debug.setListener(null);
 
 assertFalse(exception, "exception in listener")
 assertTrue(listenerComplete);