- Add String::Concat(Handle<String> left, Handle<String> right) to the V8 API...

- Add String::Concat(Handle<String> left, Handle<String> right) to the V8 API.

This is the first step to address http://crbug.com/23131 by creating
a series of V8 ConsStrings as more data arrives from the server.


Committed: http://code.google.com/p/v8/source/detail?r=3066

[Christian Plesner Hansen, 2009-10-14 08:35:57]

As I understand the issue there are two problems we're trying to solve: 1,
concatenation should not be linear and 2, we shouldn't waste so much space on
intermediate results that are kept alive from javascript.  Consing strings makes
concatenation constant but causes the contents of the string to be copied into
the v8 heap as soon as it is used.  If intermediate results are used they will
also be moved copied the heap in separate copies.

Wouldn't it be preferable to use a JSC-like model where we maintain a single
string buffer that data is incrementally added to, and then expose intermediate
results and the final result through external strings backed by this buffer but
with different lengths?

[Christian Plesner Hansen, 2009-10-14 14:39:50]

After discussing this with Ivan: Lgtm!  It seems that people usually don't use
intermediate results so this should work fine.