Revert "[NTP composebox] Keep query on close / parameterize close behavior"

This reverts commit b3e10a4c69655866f241c0319eca7587740eacb5.

Reason for revert: failing test NewTabPageAppTest.ComposeEntryPoint

Bug: 428761776, 431902891

Original change's description:
> [NTP composebox] Keep query on close / parameterize close behavior
>
> Instead of not rendering the composebox when the composebox is closed,
> we instead will just hide it. This allows for the query and stored files
> to be maintained if the composebox is opened again. Also parameterizes
> the aggressive exit behavior so we can disable it if it is unwanted.
> Also removes DCHECKs that cause crashes in dev.
>
> Bug: 428761776
> Change-Id: I8a2e0e4ed8d6399d3d1e8f24ffc8ba4d91c683ca
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6695829
> Reviewed-by: Roman Arora <romanarora@chromium.org>
> Reviewed-by: Riley Tatum <rtatum@google.com>
> Commit-Queue: Marlon Facey <mfacey@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#1486633}

Bug: 428761776
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Change-Id: Ide02289ff116b45b724f82603895be5d0ab5337f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6733149
Reviewed-by: Shunya Shishido <sisidovski@chromium.org>
Auto-Submit: Georg Neis <neis@chromium.org>
Commit-Queue: Shunya Shishido <sisidovski@chromium.org>
Owners-Override: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1486731}