Fix toolbar announce wrong text.

This is a regression during refactor toolbar code, we don't intent
to announce the toolbar popup window so we should not set content
description for the container.

Bug: 239563674
Test: manual. Turn on talkback and make sure the announce is correct
and the behavior is the same
Test: atest TextViewIntegrationTest pass for local/remote
Test: atest TextViewActivityTest pass for local/remote
Test: atest SuggestionsPopupWindowTest pass for local/remote

Change-Id: I6e30d2f6d9a2c4905b702c25655fe5e4eb7de5d5