Add a UI Feature flag for room history settings

src/settings/Settings.ts

@@ -630,6 +630,10 @@ export const SETTINGS: {[setting: string]: ISetting} = {
         supportedLevels: LEVELS_ACCOUNT_SETTINGS,
         default: null,
     },
+    [UIFeature.RoomHistorySettings]: {
+        supportedLevels: LEVELS_UI_FEATURE,
+        default: true,
+    },
     [UIFeature.AdvancedEncryption]: {
         supportedLevels: LEVELS_UI_FEATURE,
         default: true,

src/settings/UIFeature.ts

@@ -31,4 +31,5 @@ export enum UIFeature {
     Flair = "UIFeature.flair",
     Communities = "UIFeature.communities",
     AdvancedSettings = "UIFeature.advancedSettings",
+    RoomHistorySettings = "UIFeature.roomHistorySettings",
 }