[string] Don't tail-call into runtime with adaptor frames

test/mjsunit/regress/regress-688690.js

Index: test/mjsunit/regress/regress-688690.js
diff --git a/test/mjsunit/regress/regress-688690.js b/test/mjsunit/regress/regress-688690.js
new file mode 100644
index 0000000000000000000000000000000000000000..ac4eb77e232d607dd0dedb9c6cde08a98cdee434
--- /dev/null
+++ b/test/mjsunit/regress/regress-688690.js
@@ -0,0 +1,16 @@
+// 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.
+
+var foo = "01234567";
+
+foo += foo;
+foo += foo;
+foo += foo;
+foo += foo;
+foo += foo;  // foo.length = 256;
+
+// Create an adaptor frame, and take the StringReplaceOneCharWithString runtime
+// fast path. This crashed originally since TailCallRuntime could not handle
+// adaptor frames.
+var bar = foo.replace('x', 'y', 'z');