Add filtering of IPC messages when RenderFrameHost is swapped out.

BUG=351815

Review URL: https://codereview.chromium.org/205543002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@258521 0039d316-1c4b-4281-b951-d872f2087c98
void RenderFrameHostImpl::SwapOut() {
  if (render_view_host_->IsRenderViewLive()) {
    Send(new FrameMsg_SwapOut(routing_id_));
  } else {
    OnSwappedOut(true);
  }
}

void RenderFrameHostImpl::SwapOut() {
  if (render_view_host_->IsRenderViewLive()) {
    Send(new FrameMsg_SwapOut(routing_id_));
  } else {
    OnSwappedOut(true);
  }
}
