Eliminate a useless comparison in srcset's candidate selection algorithm

Eliminate a useless comparison in srcset's candidate selection algorithm
https://bugs.webkit.org/show_bug.cgi?id=120235

Source/WebCore:

There is no point in comparing the last item in the candidates vector to the DPR, since it will be returned anyway. Therefore, the
iteration on the candidates vector now skips the last candidate.

Patch by Yoav Weiss <yoav@yoav.ws> on 2013-08-24
Reviewed by Andreas Kling.

* html/parser/HTMLParserIdioms.cpp:
(WebCore::bestFitSourceForImageAttributes):

LayoutTests:

Removed MIME types from the test's output, since they're irrelevant for the test, and make it fragile.

Patch by Yoav Weiss <yoav@yoav.ws> on 2013-08-24
Reviewed by Andreas Kling.

* fast/hidpi/image-srcset-fraction-expected.txt:
* fast/hidpi/image-srcset-fraction.html:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@154548 268f45cc-cd09-0410-ab3c-d52691b4dbfc