Ensure capacity when adding parts in String.replace.

R=ulan@chromium.org
BUG=v8:2289
TEST=regress-2289.js

Review URL: https://chromiumcodereview.appspot.com/10830304

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12307 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/runtime.cc

@@ -3128,6 +3128,7 @@ MUST_USE_RESULT static MaybeObject* StringReplaceRegExpWithString(
   if (global_cache.HasException()) return Failure::Exception();
 
   if (prev < subject_length) {
+    builder.EnsureCapacity(2);
     builder.AddSubjectSlice(prev, subject_length);
   }
 

test/mjsunit/regress/regress-2289.js

+// Copyright 2012 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+var foo = "a";
+for (var i = 0; i < 12; i++) foo += foo;
+foo = foo + 'b' + foo;
+
+foo.replace(/b/, "a");
+
+