winemac: Defer adjusting window levels while the process is hidden.

While the process is hidden, it can't get a list of its windows which would
be visible were it not hidden.

dlls/winemac.drv/cocoa_app.m

@@ -488,8 +488,8 @@ - (WineWindow*) frontWineWindow
 
     - (void) adjustWindowLevels:(BOOL)active
     {
-        NSArray* windowNumbers = [NSWindow windowNumbersWithOptions:0];
-        NSMutableArray* wineWindows = [[NSMutableArray alloc] initWithCapacity:[windowNumbers count]];
+        NSArray* windowNumbers;
+        NSMutableArray* wineWindows;
         NSNumber* windowNumber;
         NSUInteger nextFloatingIndex = 0;
         __block NSInteger maxLevel = NSIntegerMin;
@@ -497,6 +497,11 @@ - (void) adjustWindowLevels:(BOOL)active
         __block WineWindow* prev = nil;
         WineWindow* window;
 
+        if ([NSApp isHidden]) return;
+
+        windowNumbers = [NSWindow windowNumbersWithOptions:0];
+        wineWindows = [[NSMutableArray alloc] initWithCapacity:[windowNumbers count]];
+
         // For the most part, we rely on the window server's ordering of the windows
         // to be authoritative.  The one exception is if the "floating" property of
         // one of the windows has been changed, it may be in the wrong level and thus
@@ -2127,6 +2132,11 @@ - (void)applicationDidResignActive:(NSNotification *)notification
         [self releaseMouseCapture];
     }
 
+    - (void) applicationDidUnhide:(NSNotification*)aNotification
+    {
+        [self adjustWindowLevels];
+    }
+
     - (BOOL) applicationShouldHandleReopen:(NSApplication*)theApplication hasVisibleWindows:(BOOL)flag
     {
         // Note that "flag" is often wrong.  WineWindows are NSPanels and NSPanels