…nager."

This reverts commit 8274acffea8d86c2d98bd058a938ff3cf21da79b.

Reason for revert: This CL made AppBannerManagerBrowserTestWithChromeBFCache.VerifyBFCacheBehavior flakey.

Bug: 331507928

Original change's description:
> [PWA] Refactoring state machine into AppBannerManager.
>
> This CL is the next incremental step into removing all of the
> inheritance in the AppBannerManager system. It does this by:
> - Move state mutation back into base class - e.g. stop calling
>   UpdateState, stop making AppBannerManager member function calls, and
>   stop other AppBannerManager member variable modification.
> - Move logic branching into base class.
>
> The goal is to not have this state machine spread across multiple
> classes, which makes it extremely hard to reason about and read.
>
> (no functional changes here)
>
> Bug: 327427513
> Change-Id: I1b082cf8e9a2d2d7eb3f393be70a5f77ae2b10d4
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5351157
> Commit-Queue: Elly FJ <ellyjones@chromium.org>
> Reviewed-by: Dibyajyoti Pal <dibyapal@chromium.org>
> Reviewed-by: Ella Ge <eirage@chromium.org>
> Auto-Submit: Daniel Murphy <dmurph@chromium.org>
> Reviewed-by: Elly FJ <ellyjones@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#1278384}

(cherry picked from commit 1f0bb4e9089cdc07521db509b63ca58c6ad175f9)

Bug: 327427513
Change-Id: I206b1499e15dca57d1e65ac98883f738a7c1a50e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5399937
Reviewed-by: Tsuyoshi Horo <horo@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Tsuyoshi Horo <horo@chromium.org>
Owners-Override: Tsuyoshi Horo <horo@chromium.org>
Cr-Original-Commit-Position: refs/heads/main@{#1278754}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5401597
Reviewed-by: Krishna Govind <govind@chromium.org>
Owners-Override: Krishna Govind <govind@chromium.org>
Cr-Commit-Position: refs/branch-heads/6382@{#6}
Cr-Branched-From: 12485c548bb8b29a4c26fbfe59bc108444521bca-refs/heads/main@{#1278683}