Revert "Rerender MessagePanel"

This reverts commit c7e61ac71d.

src/components/views/messages/TextualBody.js

@@ -147,10 +147,6 @@ export default class TextualBody extends React.Component {
                 pre.className = "mx_EventTile_collapsedCodeBlock";
                 button.className += "mx_EventTile_expandButton";
             }
-            /* Now we need to rerender the MessagePanel because the
-             * content's size has changed. Otherwise scrolling could
-             * get broken */
-            dis.dispatch({action: "rerender_MessagePanel"});
         };
 
         div.appendChild(button);