[Presentation API] Add layout test for connection.close() and fix test failures

Add layout test.

1-UA connection.close() hits NOTREACHED() in PresentationConnection::didChangeState(). Use PresentationConnection::didClose() instead.

BUG=697719

Review-Url: https://codereview.chromium.org/2730123003
Cr-Commit-Position: refs/heads/master@{#455225}
PresentationConnection* PresentationConnection::take(
    PresentationReceiver* receiver,
    const WebPresentationSessionInfo& sessionInfo) {
  DCHECK(receiver);

  PresentationConnection* connection = new PresentationConnection(
      receiver->frame(), sessionInfo.id, sessionInfo.url);
  receiver->registerConnection(connection);

  return connection;
}

PresentationConnection* PresentationConnection::take(
    PresentationReceiver* receiver,
    const WebPresentationSessionInfo& sessionInfo) {
  DCHECK(receiver);

  PresentationConnection* connection = new PresentationConnection(
      receiver->frame(), sessionInfo.id, sessionInfo.url);
  receiver->registerConnection(connection);

  return connection;
}
