Replace yield() and pauseBriefly() with std::this_thread::yield()
https://bugs.webkit.org/show_bug.cgi?id=126105

Reviewed by Sam Weinig.

Source/WebCore:

* platform/sql/SQLiteDatabase.cpp:
(WebCore::SQLiteDatabase::interrupt):

Source/WTF:

* wtf/ByteSpinLock.h:
(WTF::ByteSpinLock::lock):
* wtf/Threading.h:
* wtf/ThreadingPrimitives.h:
* wtf/ThreadingPthreads.cpp:
* wtf/ThreadingWin.cpp:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@160959 268f45cc-cd09-0410-ab3c-d52691b4dbfc