JavaScriptCore:

JavaScriptCore:

        Reviewed by Geoff.

        - Correctly report cost of appended strings to trigger GC.

        * kjs/ustring.cpp:
        (KJS::):
        (KJS::UString::Rep::create):
        (KJS::UString::UString): Don't create unnecssary objects.
        (KJS::UString::cost): Report cost if necessary but also keep track of
        reported cost.
        * kjs/ustring.h:

LayoutTests:

        Reviewed by Geoff.

        - Correctly report cost of appended strings to trigger GC.

        * fast/js/garbage-collect-after-string-appends-expected.txt: Added.
        * fast/js/garbage-collect-after-string-appends.html: Added.
        * fast/js/resources/garbage-collect-after-string-appends.js: Added.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@29639 268f45cc-cd09-0410-ab3c-d52691b4dbfc