deps: backport 7c3748a from upstream V8

Original commit message:
  [debug] load correct stack slot for frame details.

  R=bmeurer@chromium.org
  BUG=v8:5071

  Review URL: https://codereview.chromium.org/2045863002 .

  Cr-Commit-Position: refs/heads/master@{#36769}

PR-URL: #10873
Reviewed-By: bnoordhuis - Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: jasnell - James M Snell <jasnell@gmail.com>
Reviewed-By: ofrobots - Ali Ijaz Sheikh <ofrobots@google.com>

deps/v8/include/v8-version.h

@@ -11,7 +11,7 @@
 #define V8_MAJOR_VERSION 4
 #define V8_MINOR_VERSION 5
 #define V8_BUILD_NUMBER 103
-#define V8_PATCH_LEVEL 45
+#define V8_PATCH_LEVEL 46
 
 // Use 1 for candidates and 0 otherwise.
 // (Boolean macro values are not supported by all preprocessors.)

deps/v8/src/runtime/runtime-debug.cc

@@ -670,7 +670,8 @@ RUNTIME_FUNCTION(Runtime_GetFrameDetails) {
     // Use the value from the stack.
     if (scope_info->LocalIsSynthetic(i)) continue;
     locals->set(local * 2, scope_info->LocalName(i));
-    locals->set(local * 2 + 1, frame_inspector.GetExpression(i));
+    locals->set(local * 2 + 1,
+            frame_inspector.GetExpression(scope_info->StackLocalIndex(i)));
     local++;
   }
   if (local < local_count) {

deps/v8/test/mjsunit/regress/regress-5071.js

@@ -0,0 +1,27 @@
+// Copyright 2016 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.
+
+// Flags: --expose-debug-as debug
+
+'use strict';
+var Debug = debug.Debug;
+
+function listener(event, exec_state, event_data, data) {
+  assertEquals(2, exec_state.frameCount());
+  assertEquals("a", exec_state.frame(0).localName(0));
+  assertEquals("1", exec_state.frame(0).localValue(0).value());
+  assertEquals(1, exec_state.frame(0).localCount());
+}
+
+Debug.setListener(listener);
+
+function f() {
+  var a = 1;
+  {
+    let b = 2;
+    debugger;
+  }
+}
+
+f();