New debug scheme with explicit debug channels declaration.

diff --git a/windows/message.c b/windows/message.c
index f188849..96072a1 100644
--- a/windows/message.c
+++ b/windows/message.c
@@ -30,6 +30,10 @@
 #include "struct32.h"
 #include "debug.h"
 
+DECLARE_DEBUG_CHANNEL(key)
+DECLARE_DEBUG_CHANNEL(msg)
+DECLARE_DEBUG_CHANNEL(sendmsg)
+
 #define WM_NCMOUSEFIRST         WM_NCMOUSEMOVE
 #define WM_NCMOUSELAST          WM_NCMBUTTONDBLCLK