Attempted fix for a crash reported on Discord

Author: emilk

epaint/src/text/text_layout.rs

@@ -172,7 +172,9 @@ fn rows_from_paragraphs(
                 });
             } else {
                 line_break(fonts, &paragraph, job, &mut rows);
-                rows.last_mut().unwrap().ends_with_newline = !is_last_paragraph;
+                if let Some(last_row) = rows.last_mut() {
+                    last_row.ends_with_newline = !is_last_paragraph;
+                }
             }
         }
     }