Add bounds-checking in runtime implementations of %FixedArray{Get,Set}

test/mjsunit/regress/regress-504786.js

Index: test/mjsunit/regress/regress-504786.js
diff --git a/test/mjsunit/regress/regress-504786.js b/test/mjsunit/regress/regress-504786.js
new file mode 100644
index 0000000000000000000000000000000000000000..f794645c2b0cc950f464eb480b5117f1622b3393
--- /dev/null
+++ b/test/mjsunit/regress/regress-504786.js
@@ -0,0 +1,10 @@
+// Copyright 2015 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
+
+var a = %GetTypeFeedbackVector(function(){});
+// The runtime versions of these intrinsics include bounds-checking.
+assertThrows(function() { %FixedArrayGet(a, 0xffff) });
+assertThrows(function() { %FixedArraySet(a, 53894378, 0) });