Split wxWakeUpPipe class in MT-unsafe and MT-safe parts.

This class can also be useful when it's used in the main thread only, so
leave the lock-less part of the code in wxWakeUpPipe and derive a separate
wxWakeUpPipeMT from it for the use in wxConsoleEventLoop where it can be used
by multiple threads.

See #10258.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74339 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/unix/wakeuppipe.cpp

@@ -69,10 +69,8 @@ wxWakeUpPipe::wxWakeUpPipe()
 // wakeup handling
 // ----------------------------------------------------------------------------
 
-void wxWakeUpPipe::WakeUp()
+void wxWakeUpPipe::WakeUpNoLock()
 {
-    wxCriticalSectionLocker lock(m_pipeLock);
-
     // No need to do anything if the pipe already contains something.
     if ( !m_pipeIsEmpty )
       return;
@@ -95,8 +93,6 @@ void wxWakeUpPipe::OnReadWaiting()
     // got wakeup from child thread, remove the data that provoked it from the
     // pipe
 
-    wxCriticalSectionLocker lock(m_pipeLock);
-
     char buf[4];
     for ( ;; )
     {