Correctly resolve local var shadowing a context-allocated var in debugger.

test/mjsunit/regress/regress-131994.js

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 // Flags: --expose-debug-as debug
 
+// Test that a variable in the local scope that shadows a context-allocated
+// variable is correctly resolved when being evaluated in the debugger.
+
 Debug = debug.Debug;
 
 var exception = false;
 
 function listener(event, exec_state, event_data, data) {
+  if (event != Debug.DebugEvent.Break) return;
+  var breakpoint = exec_state.frame(0);
   try {
-    if (event == Debug.DebugEvent.Break) {
-      function lookup(name) {
-        return exec_state.frame(0).evaluate(name).value();
-      }
-
-      assertEquals(3, lookup("e"));
-      assertEquals(4, lookup("f"));
-      assertEquals(1, lookup("a"));
-
-      try {
-        assertEquals(2, lookup("b"));
-      } catch (e) {
-        assertEquals("ReferenceError: b is not defined", e.toString());
-      }
-    }
+    // Assert correct break point.
+    assertTrue(breakpoint.sourceLineText().indexOf("// Break") > -1);
+    // Assert correct value.
+    assertEquals(3, breakpoint.evaluate('x').value());
   } catch (e) {
-    exception = e.toString() + e.stack;
+    exception = e;
   }
 }
 
 Debug.setListener(listener);
 
-function f(a, b) {
-  var c = 3;
-  function d(e, f) {
-    var g = a;
-    var h = c;
-    debugger;
-  }
+function h() {
+  var x;  // Context-allocated due to g().
 
-  return d;
+  var g = function g() {
+    x = -7;
+  };
+
+  var f = function f() {
+    var x = 3;  // Allocated in the local scope.
+    debugger;  // Break.
+  };
+
+  f();
 }
 
-f(1, 2)(3, 4);
+h();
 
 assertFalse(exception);
+