Autocomplete slow to update with large data sets after material beta 12

#### Bug, feature request, or proposal:
When displaying an autocomplete list with a large number of options it is slow to display. It appears that this is caused by 2 event listeners being created for each item in the list. This slowness started after updating to beta 12.

You can see the large number of event listeners being set up if you open the Chrome dev tools and set the logging level to verbose.
`[Violation] Added non-passive event listener to a scroll-blocking 'touchstart' event. Consider marking event handler as 'passive' to make the page more responsive. See https://www.chromestatus.com/feature/5745543795965952`

#### What is the expected behavior?
Similar performance when using autocomplete with 200+ data sets to older versions of material.

#### What is the current behavior?
Rendering an autocomplete with a large number of options has a delay, it is even longer when the dev tools are open due to the large number of event listeners being created causing logs to be written to the console

#### What are the steps to reproduce?
Open dev tools, set console logging to verbose and click the "Click to toggle autocomplete" button .
You can also see the behavior by filtering the list, type anything to shorten the length of the list, then clear the input and new event listeners will be created again for each item in the list causing additional slowdown.
https://plnkr.co/edit/QhlHy7FrlvQbDeRfncCo?p=preview

#### What is the use-case or motivation for changing an existing behavior?
Improve performance. Is it not possible to have a single event listener on the parent that catches click events that bubble up? If not do 2 event listeners need to be created for each item in the list?

#### Which versions of Angular, Material, OS, TypeScript, browsers are affected?
Angular: 4.4.4
Material: beta.12
All browsers

#### Is there anything else we should know?
Event handler times on beta.11
Clearing out the input box, causing all items to be displayed again
`[Violation] 'input' handler took 187ms`
Clicking the button to display the autocomplete
`[Violation] 'click' handler took 246ms`

Event handler times on beta.12 doing the same actions
`[Violation] 'input' handler took 1347ms`
`[Violation] 'click' handler took 1048ms`

リンク先の Plunker で autocomplete の再現から始め、Chrome DevTools の詳細ログを使用して beta.12 と beta.11 を比較します。リストを開く、フィルタリングする、クリアする際の listener の作成を追跡します。大規模なオプションセットで報告されている listener 関連の遅延が発生しなくなり、event-handler の時間が以前のバージョンと同程度になれば完了です。

索引モデルが issue の本文から書いたものです。