[turbofan] Add toLowerCase, toUpperCase operators to the infamous escape analysis list.

BUG=chromium:733181

Review-Url: https://codereview.chromium.org/2962853002
Cr-Commit-Position: refs/heads/master@{#46279}

src/compiler/escape-analysis.cc

@@ -838,6 +838,8 @@ bool EscapeStatusAnalysis::CheckUsesForEscape(Node* uses, Node* rep,
       case IrOpcode::kStringCharCodeAt:
       case IrOpcode::kSeqStringCharCodeAt:
       case IrOpcode::kStringIndexOf:
+      case IrOpcode::kStringToLowerCaseIntl:
+      case IrOpcode::kStringToUpperCaseIntl:
       case IrOpcode::kObjectIsDetectableCallable:
       case IrOpcode::kObjectIsNaN:
       case IrOpcode::kObjectIsNonCallable:

test/mjsunit/compiler/regress-733181.js

+// Copyright 2017 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 l(s) {
+  return ("xxxxxxxxxxxxxxxxxxxxxxx" + s).toLowerCase();
+}
+
+l("abcd");
+l("abcd");
+%OptimizeFunctionOnNextCall(l);
+l("abcd");
+
+function u(s) {
+  return ("xxxxxxxxxxxxxxxxxxxxxxx" + s).toUpperCase();
+}
+
+u("abcd");
+u("abcd");
+%OptimizeFunctionOnNextCall(u);
+u("abcd");