add flag/hint to PlatformGetSpecific. If true, then the caller requires that
the tls slot be allocated even if this is the first, to ensure that it can
later call PlatformSetSpecific. When this is false (which is most of the time)
the implementation may optimize by not even creating the slot, and just
returning null.



git-svn-id: http://skia.googlecode.com/svn/trunk@3871 2bbb7eff-a529-9590-31e7-b0007b416f81
5 files changed