message: don't focus composer on keydown with modifier
  this breaks shortcuts like copy, ...
diff: @@ -326,11 +326,12 @@ const LoggedInView = React.createClass({
  let handled = false;
  const ctrlCmdOnly = isOnlyCtrlOrCmdKeyEvent(ev);
  + const hasModifier = ev.altKey || ev.ctrlKey || ev.metaKey || ev.shiftKey;
  switch (ev.keyCode) {
  case KeyCode.PAGE_UP:
  case KeyCode.PAGE_DOWN:
  - if (!ev.ctrlKey && !ev.shiftKey && !ev.altKey && !ev.metaKey) {
  + if (!hasModifier) {
  this._onScrollKeyPressed(ev);
  handled = true;
  }
  @@ -369,7 +370,7 @@ const LoggedInView = React.createClass({
  if (handled) {
  ev.stopPropagation();
  ev.preventDefault();
  - } else {
  + } else if (!hasModifier) {
  const targetTag = ev.target.tagName;
  const focusedOnInputControl = targetTag === "INPUT" ||
  targetTag === "TEXTAREA" ||
  