Include winuser.h so the code compiles cleanly on windows using

dlls/dsound/buffer.c

@@ -25,6 +25,7 @@
 #define NONAMELESSUNION
 #include "windef.h"
 #include "winbase.h"
+#include "winuser.h"
 #include "mmsystem.h"
 #include "winreg.h"
 #include "winternl.h"

dlls/dsound/capture.c

@@ -31,6 +31,7 @@
 #define NONAMELESSUNION
 #include "windef.h"
 #include "winbase.h"
+#include "winuser.h"
 #include "mmsystem.h"
 #include "mmddk.h"
 #include "winreg.h"

dlls/dsound/dsound.c

@@ -27,6 +27,7 @@
 #define NONAMELESSUNION
 #include "windef.h"
 #include "winbase.h"
+#include "winuser.h"
 #include "winreg.h"
 #include "mmsystem.h"
 #include "winternl.h"

dlls/dsound/dsound_main.c

@@ -43,6 +43,7 @@
 #define NONAMELESSUNION
 #include "windef.h"
 #include "winbase.h"
+#include "winuser.h"
 #include "winnls.h"
 #include "winreg.h"
 #include "mmsystem.h"

dlls/dsound/duplex.c

@@ -30,6 +30,7 @@
 #define NONAMELESSUNION
 #include "windef.h"
 #include "winbase.h"
+#include "winuser.h"
 #include "mmsystem.h"
 #include "mmddk.h"
 #include "winreg.h"

dlls/dsound/mixer.c

@@ -27,6 +27,7 @@
 #define NONAMELESSUNION
 #include "windef.h"
 #include "winbase.h"
+#include "winuser.h"
 #include "mmsystem.h"
 #include "winreg.h"
 #include "winternl.h"

dlls/dsound/primary.c

@@ -25,6 +25,7 @@
 #define NONAMELESSUNION
 #include "windef.h"
 #include "winbase.h"
+#include "winuser.h"
 #include "mmsystem.h"
 #include "winreg.h"
 #include "winternl.h"

dlls/dsound/propset.c

@@ -23,6 +23,7 @@
 
 #include "windef.h"
 #include "winbase.h"
+#include "winuser.h"
 #include "mmsystem.h"
 #include "winreg.h"
 #include "winternl.h"

dlls/dsound/sound3d.c

@@ -44,6 +44,7 @@
 #define NONAMELESSSTRUCT
 #include "windef.h"
 #include "winbase.h"
+#include "winuser.h"
 #include "mmsystem.h"
 #include "winreg.h"
 #include "winternl.h"