Remove thread_affinity flag and access methods.

Specificaly, remove access methods in worker_fiber, fiber and this_fiber.

thread_affinity is not used by any present library code. It was intended for
use by workstealing user sched_algorithm implementations. The properties
mechanism is a better way to address scheduler-specific properties.

include/boost/fiber/detail/flags.hpp

@@ -23,8 +23,7 @@ enum flag_t
 {
     flag_interruption_blocked   = 1 << 0,
     flag_interruption_requested = 1 << 1,
-    flag_thread_affinity = 1 << 2,
-    flag_detached = 1 << 3
+    flag_detached = 1 << 2
 };
 
 }}}

include/boost/fiber/detail/worker_fiber.hpp

@@ -129,11 +129,6 @@ public:
 
     void request_interruption( bool req) BOOST_NOEXCEPT;
 
-    bool thread_affinity() const BOOST_NOEXCEPT
-    { return 0 != ( flags_.load() & flag_thread_affinity); }
-
-    void thread_affinity( bool req) BOOST_NOEXCEPT;
-
     bool is_terminated() const BOOST_NOEXCEPT
     { return TERMINATED == state_; }
 

include/boost/fiber/fiber.hpp

@@ -312,10 +312,6 @@ public:
 
     void priority( int) BOOST_NOEXCEPT;
 
-    bool thread_affinity() const BOOST_NOEXCEPT;
-
-    void thread_affinity( bool) BOOST_NOEXCEPT;
-
     void detach() BOOST_NOEXCEPT;
 
     void join();

include/boost/fiber/operations.hpp

@@ -64,21 +64,6 @@ template< typename Rep, typename Period >
 void sleep_for( chrono::duration< Rep, Period > const& timeout_duration)
 { sleep_until( chrono::high_resolution_clock::now() + timeout_duration); }
 
-inline
-bool thread_affinity() BOOST_NOEXCEPT
-{
-    return 0 != fibers::fm_active()
-        ? fibers::fm_active()->thread_affinity()
-        : true;
-}
-
-inline
-void thread_affinity( bool req) BOOST_NOEXCEPT
-{
-    if ( 0 != fibers::fm_active() )
-        fibers::fm_active()->thread_affinity( req);
-}
-
 template < class PROPS >
 PROPS& properties()
 {

src/detail/worker_fiber.cpp

@@ -97,15 +97,6 @@ worker_fiber::request_interruption( bool req) BOOST_NOEXCEPT
         flags_ &= ~flag_interruption_requested;
 }
 
-void
-worker_fiber::thread_affinity( bool req) BOOST_NOEXCEPT
-{
-    if ( req)
-        flags_ |= flag_thread_affinity;
-    else
-        flags_ &= ~flag_thread_affinity;
-}
-
 void *
 worker_fiber::get_fss_data( void const* vp) const
 {

src/fiber.cpp

@@ -44,22 +44,6 @@ fiber::priority( int prio) BOOST_NOEXCEPT
     fm_priority( impl_.get(), prio);
 }
 
-bool
-fiber::thread_affinity() const BOOST_NOEXCEPT
-{
-    BOOST_ASSERT( impl_);
-
-    return impl_->thread_affinity();
-}
-
-void
-fiber::thread_affinity( bool req) BOOST_NOEXCEPT
-{
-    BOOST_ASSERT( impl_);
-
-    impl_->thread_affinity( req);
-}
-
 void
 fiber::join()
 {