X11 messageboxes should treat "\r\n" as "\n" by ignoring the '\r' char.

--HG--
extra : rebase_source : 0054e96755f753555237f3d7dd64f1dfa1a1e56c

src/video/x11/SDL_x11messagebox.c

@@ -250,6 +250,10 @@ X11_MessageBoxInitPositions( SDL_MessageBoxDataX11 *data )
             data->text_height = IntMax( data->text_height, height );
             text_width_max = IntMax( text_width_max, plinedata->width );
 
+            if (lf && (lf > text) && (lf[-1] == '\r')) {
+                plinedata->length--;
+            }
+
             text += plinedata->length + 1;
 
             /* Break if there are no more linefeeds. */

test/testmessage.c

@@ -49,6 +49,15 @@ main(int argc, char *argv[])
         quit(1);
     }
 
+    success = SDL_ShowSimpleMessageBox(SDL_MESSAGEBOX_ERROR,
+                "Simple MessageBox",
+                "This is a simple MessageBox with a newline:\r\nHello world!",
+                NULL);
+    if (success == -1) {
+        printf("Error Presenting MessageBox: %s\n", SDL_GetError());
+        quit(1);
+    }
+
     /* Google says this is Traditional Chinese for "beef with broccoli" */
     success = SDL_ShowSimpleMessageBox(SDL_MESSAGEBOX_ERROR,
                 "UTF-8 Simple MessageBox",
@@ -59,6 +68,16 @@ main(int argc, char *argv[])
         quit(1);
     }
 
+    /* Google says this is Traditional Chinese for "beef with broccoli" */
+    success = SDL_ShowSimpleMessageBox(SDL_MESSAGEBOX_ERROR,
+                "UTF-8 Simple MessageBox",
+                "Unicode text and newline:\r\n'牛肉西蘭花'\n'牛肉西蘭花'",
+                NULL);
+    if (success == -1) {
+        printf("Error Presenting MessageBox: %s\n", SDL_GetError());
+        quit(1);
+    }
+
     {
         const SDL_MessageBoxButtonData buttons[] = {
             {