Correctly set the length of string before creating filler object in the json...

Correctly set the length of string before creating filler object in the json parser (fixes crbug 84186).

Testcase created based on the supplied test case from the bug report, but using json parse directly instead of through the chrome javascript console. 
Review URL: http://codereview.chromium.org/7084023

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8089 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/json-parser.cc

@@ -453,6 +453,7 @@ Token::Value JsonParser::SlowScanJsonString() {
         SeqTwoByteString::SizeFor(kInitialSpecialStringSize * allocation_count);
     int delta = allocated_string_size - string_size;
     Address start_filler_object = seq_two_byte->address() + string_size;
+    seq_two_byte->set_length(count);
     isolate()->heap()->CreateFillerObjectAt(start_filler_object, delta);
   }
   string_val_ = isolate()->factory()->NewConsString(ascii, seq_two_byte);

test/mjsunit/regress/regress-crbug-84186.js

+// Copyright 2011 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.
+
+// Test that the expected string is parsed in the json parser when the length
+// is so big that the string can't fit in new space, and it includes special
+// characters.
+
+var json = '{"key":"';
+var key = '';
+var expected = '';
+for(var i = 0; i < 60000; i++) {
+  key = key + "TESTING" + i + "\\n";
+  expected = expected + "TESTING" + i + "\n";
+}
+json = json + key  + '"}';
+var out = JSON.parse(json);
+assertEquals(expected, out.key);