Removing m_maxDeadCapacity condition in fast path in MemoryCache::prune().
https://bugs.webkit.org/show_bug.cgi?id=115631

Patch by Marcin Bychawski <m.bychawski@samsung.com> on 2013-10-31
Reviewed by Brent Fulgham.

If the m_maxDeadSize and m_deadSize are both 0, the method unnecessairly tries to prune resources.

No new tests, covered by existing ones.

* loader/cache/MemoryCache.cpp:
(WebCore::MemoryCache::prune):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@158357 268f45cc-cd09-0410-ab3c-d52691b4dbfc