getProcessIdForTab method
Returns the ID of the renderer process for the specified tab. |tabId|: The ID of the tab for which the renderer process ID is to be returned.
Implementation
Future<int> getProcessIdForTab(int tabId) async {
  var $res = await promiseToFuture<int>(
      $js.chrome.processes.getProcessIdForTab(tabId));
  return $res;
}