Remove "history may be shared" banner. (#31881)

* Revert "Update algorithm for history visible banner. (#31577)"

This reverts commit ce9c66ba4c.

* Revert "Update prop type & documentation for HistoryVisibleBanner and VM. (#31545)"

This reverts commit 4da149e56f.

* Revert "Prevent history visible banner from displaying in threads. (#31535)"

This reverts commit c7134e8532.

* Revert "Implement UI for history visibility acknowledgement. (#31156)"

This reverts commit cff9119324.

test/test-utils/test-utils.ts

@@ -9,7 +9,6 @@ Please see LICENSE files in the repository root for full details.
 import EventEmitter from "events";
 import { mocked, type MockedObject } from "jest-mock";
 import {
-    type EventTimeline,
     MatrixEvent,
     type Room,
     type User,
@@ -17,7 +16,7 @@ import {
     type IEvent,
     type RoomMember,
     type MatrixClient,
-    RoomState,
+    type EventTimeline,
     EventType,
     type IEventRelation,
     type IUnsigned,
@@ -30,9 +29,9 @@ import {
     JoinRule,
     type OidcClientConfig,
     type GroupCall,
-    HistoryVisibility,
-    type ICreateRoomOpts,
     type EventStatus,
+    type ICreateRoomOpts,
+    RoomState,
 } from "matrix-js-sdk/src/matrix";
 import { KnownMembership } from "matrix-js-sdk/src/types";
 import { normalize } from "matrix-js-sdk/src/utils";
@@ -668,7 +667,6 @@ export function mkStubRoom(
         createThreadsTimelineSets: jest.fn().mockReturnValue(new Promise(() => {})),
         currentState: {
             getStateEvents: jest.fn((_type, key) => (key === undefined ? [] : null)),
-            getHistoryVisibility: jest.fn().mockReturnValue(HistoryVisibility.Joined),
             getMember: jest.fn(),
             mayClientSendStateEvent: jest.fn().mockReturnValue(true),
             maySendStateEvent: jest.fn().mockReturnValue(true),
@@ -689,7 +687,6 @@ export function mkStubRoom(
         getCanonicalAlias: jest.fn(),
         getDMInviter: jest.fn(),
         getEventReadUpTo: jest.fn(() => null),
-        getHistoryVisibility: jest.fn().mockReturnValue(HistoryVisibility.Joined),
         getInvitedAndJoinedMemberCount: jest.fn().mockReturnValue(1),
         getJoinRule: jest.fn().mockReturnValue("invite"),
         getJoinedMemberCount: jest.fn().mockReturnValue(1),