Avoid hydrogen compare-objects-equal assertions in dead code

test/mjsunit/regress/regress-359491.js

+// Copyright 2014 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: --allow-natives-syntax
+
+function f(a, b, mode) {
+  if (mode) {
+    return a === b;
+  } else {
+    return a === b;
+  }
+}
+
+// Gather type feedback for both branches.
+f("a", "b", 1);
+f("c", "d", 1);
+f("a", "b", 0);
+f("c", "d", 0);
+
+function g(mode) {
+  var x = 1e10 | 0;
+  f(x, x, mode);
+}
+
+// Gather type feedback for g, but only on one branch for f.
+g(1);
+g(1);
+%OptimizeFunctionOnNextCall(g);
+// Optimize g, which inlines f. Both branches in f will see the constant.
+g(0);