task: get rid of the insert_task method

Nothing calls it (not even tests), and there's significant functional
overlap with `try_lock`.

Signed-off-by: Zygo Blaxell <bees@furryterror.org>

include/crucible/task.h

@@ -172,9 +172,6 @@ namespace crucible {
 		/// objects it holds, and exit its Task function.
 		ExclusionLock try_lock(const Task &task);
 
-		/// Execute Task when Exclusion is unlocked (possibly
-		/// immediately).
-		void insert_task(const Task &t);
 	};
 
 	/// Wrapper around pthread_setname_np which handles length limits

lib/task.cc

@@ -936,21 +936,6 @@ namespace crucible {
 		m_owner.reset();
 	}
 
-	void
-	Exclusion::insert_task(const Task &task)
-	{
-		unique_lock<mutex> lock(m_mutex);
-		const auto sp = m_owner.lock();
-		lock.unlock();
-		if (sp) {
-			// If Exclusion is locked then queue task for release;
-			sp->append(task);
-		} else {
-			// otherwise, run the inserted task immediately
-			task.run();
-		}
-	}
-
 	ExclusionLock
 	Exclusion::try_lock(const Task &task)
 	{