comctl32/tests: Flush pending events before progress repaint tests.

dlls/comctl32/tests/progress.c

@@ -33,6 +33,21 @@ static HWND hProgressParentWnd, hProgressWnd;
 static const char progressTestClass[] = "ProgressBarTestClass";
 
 
+/* try to make sure pending X events have been processed before continuing */
+static void flush_events(void)
+{
+    MSG msg;
+    int diff = 100;
+    DWORD time = GetTickCount() + diff;
+
+    while (diff > 0)
+    {
+        if (MsgWaitForMultipleObjects( 0, NULL, FALSE, min(10,diff), QS_ALLINPUT ) == WAIT_TIMEOUT) break;
+        while (PeekMessage( &msg, 0, 0, 0, PM_REMOVE )) DispatchMessage( &msg );
+        diff = time - GetTickCount();
+    }
+}
+
 static LRESULT CALLBACK ProgressTestWndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
 {
     switch(msg) {
@@ -113,6 +128,7 @@ static void init(void)
     
     ShowWindow(hProgressParentWnd, SW_SHOWNORMAL);
     ok(GetUpdateRect(hProgressParentWnd, NULL, FALSE), "GetUpdateRect: There should be a region that needs to be updated\n");
+    flush_events();
     update_window(hProgressParentWnd);    
 }