Introduce InternalPackedArray.

src/messages.js

Index: src/messages.js
diff --git a/src/messages.js b/src/messages.js
index 4a8143e611162a447436ecb64aefb670e10c14fb..0d9c90d365f5b117dd89e9c5abc97b761fb121c9 100644
--- a/src/messages.js
+++ b/src/messages.js
@@ -557,7 +557,7 @@ function ScriptNameOrSourceURL() {
     // Don't reuse lastMatchInfo here, so we create a new array with room
     // for four captures (array with length one longer than the index
     // of the fourth capture, where the numbering is zero-based).
-    var matchInfo = new InternalArray(CAPTURE(3) + 1);
+    var matchInfo = new InternalPackedArray(CAPTURE(3) + 1);

[danno, 2013/02/15 17:35:10]

I don't think this is safe. This isn't a single element array you're creating,
but rather an array of size CAPTURE(3) + 1. Calling the
InternalPackedArray(size) constructor creates a holy array if the size isn't
zero, which is always the case here, isn't it?

     var match =
         %_RegExpExec(sourceUrlPattern, source, sourceUrlPos - 4, matchInfo);
     if (match) {
@@ -1033,7 +1033,7 @@ function FormatErrorString(error) {
 
 
 function GetStackFrames(raw_stack) {
-  var frames = new InternalArray();
+  var frames = new InternalPackedArray();
   for (var i = 0; i < raw_stack.length; i += 4) {
     var recv = raw_stack[i];
     var fun = raw_stack[i + 1];
@@ -1047,7 +1047,7 @@ function GetStackFrames(raw_stack) {
 
 
 function FormatStackTrace(error_string, frames) {
-  var lines = new InternalArray();
+  var lines = new InternalPackedArray();
   lines.push(error_string);
   for (var i = 0; i < frames.length; i++) {
     var frame = frames[i];