Revert "Revert using an event object for waking up event loop in wxMSW"

This reverts commit ebb3a791b9,
effectively reapplying 6c40531fb7 once
again.

This breaks wake up when not running our own event loop once again
(see #17579), but this will be fixed in the next commit.

include/wx/msw/evtloopconsole.h

@@ -15,9 +15,20 @@ class WXDLLIMPEXP_BASE wxMSWEventLoopBase : public wxEventLoopManual
 {
 public:
     wxMSWEventLoopBase();
+    virtual ~wxMSWEventLoopBase();
 
     // implement base class pure virtuals
     virtual bool Pending() const wxOVERRIDE;
+    virtual void WakeUp() wxOVERRIDE;
+
+#if wxUSE_THREADS
+    // MSW-specific method to wait for the termination of the specified (by its
+    // native handle) thread or any input message arriving (in GUI case).
+    //
+    // Return value is WAIT_OBJECT_0 if the thread terminated, WAIT_OBJECT_0+1
+    // if a message arrived with anything else indicating an error.
+    WXDWORD MSWWaitForThread(WXHANDLE hThread);
+#endif // wxUSE_THREADS
 
 protected:
     // get the next message from queue and return true or return false if we
@@ -25,8 +36,13 @@ protected:
     bool GetNextMessage(WXMSG *msg);
 
     // same as above but with a timeout and return value can be -1 meaning that
-    // time out expired in addition to
+    // time out expired in addition to true/false
     int GetNextMessageTimeout(WXMSG *msg, unsigned long timeout);
+
+private:
+    // An auto-reset Win32 event which is signalled when we need to wake up the
+    // main thread waiting in GetNextMessage[Timeout]().
+    WXHANDLE m_heventWake;
 };
 
 #if wxUSE_CONSOLE_EVENTLOOP
@@ -39,7 +55,6 @@ public:
     // override/implement base class virtuals
     virtual bool Dispatch() wxOVERRIDE;
     virtual int DispatchTimeout(unsigned long timeout) wxOVERRIDE;
-    virtual void WakeUp() wxOVERRIDE;
 
     // Windows-specific function to process a single message
     virtual void ProcessMessage(WXMSG *msg);