remove a few stale NULL message/title checks after commit e2b729b1756a

top-level guarantees non-NULL message / title passed in messageboxdata

src/video/cocoa/SDL_cocoamessagebox.m

@@ -113,7 +113,7 @@ Cocoa_ShowMessageBox(const SDL_MessageBoxData *messageboxdata, int *buttonid)
     int i;
     for (i = 0; i < messageboxdata->numbuttons; ++i) {
         const SDL_MessageBoxButtonData *sdlButton;
-		NSButton *button;
+        NSButton *button;
 
         if (messageboxdata->flags & SDL_MESSAGEBOX_BUTTONS_RIGHT_TO_LEFT) {
             sdlButton = &messageboxdata->buttons[messageboxdata->numbuttons - 1 - i];
@@ -142,8 +142,8 @@ Cocoa_ShowMessageBox(const SDL_MessageBoxData *messageboxdata, int *buttonid)
     if (clicked >= NSAlertFirstButtonReturn) {
         clicked -= NSAlertFirstButtonReturn;
         if (messageboxdata->flags & SDL_MESSAGEBOX_BUTTONS_RIGHT_TO_LEFT) {
-			clicked = messageboxdata->numbuttons - 1 - clicked;
-		}
+            clicked = messageboxdata->numbuttons - 1 - clicked;
+        }
         *buttonid = buttons[clicked].buttonid;
     } else {
         returnValue = SDL_SetError("Did not get a valid `clicked button' id: %ld", (long)clicked);

src/video/haiku/SDL_bmessagebox.cc

@@ -154,9 +154,9 @@ class HAIKU_SDL_MessageBox : public BAlert
 			ApplyAndParseColorScheme(aMessageBoxData->colorScheme);
 		}
 
-		(aMessageBoxData->title && aMessageBoxData->title[0]) ?
+		(aMessageBoxData->title[0]) ?
 			SetTitle(aMessageBoxData->title) : SetTitle(HAIKU_SDL_DefTitle);
-		(aMessageBoxData->message && aMessageBoxData->message[0]) ?
+		(aMessageBoxData->message[0]) ?
 			SetMessageText(aMessageBoxData->message) : SetMessageText(HAIKU_SDL_DefMessage);
 
 		SetType(ConvertMessageBoxType(static_cast<SDL_MessageBoxFlags>(aMessageBoxData->flags)));

src/video/windows/SDL_windowsmessagebox.c

@@ -314,7 +314,7 @@ static SDL_bool AddDialogControl(WIN_DialogData *dialog, WORD type, DWORD style,
     if (!AddDialogData(dialog, &type, sizeof(type))) {
         return SDL_FALSE;
     }
-    if (type == DLGITEMTYPEBUTTON || (type == DLGITEMTYPESTATIC && caption != NULL && caption[0])) {
+    if (type == DLGITEMTYPEBUTTON || (type == DLGITEMTYPESTATIC && caption[0])) {
         if (!AddDialogString(dialog, caption)) {
             return SDL_FALSE;
         }

src/video/x11/SDL_x11messagebox.c

@@ -245,7 +245,7 @@ X11_MessageBoxInitPositions( SDL_MessageBoxDataX11 *data )
     const SDL_MessageBoxData *messageboxdata = data->messageboxdata;
 
     /* Go over text and break linefeeds into separate lines. */
-    if ( messageboxdata->message && messageboxdata->message[ 0 ] ) {
+    if ( messageboxdata->message[0] ) {
         const char *text = messageboxdata->message;
         const int linecount = CountLinesOfText(text);
         TextLineData *plinedata = (TextLineData *) SDL_malloc(sizeof (TextLineData) * linecount);