Modularise legal state (#42717)

Fixes #42455.

client/state/legal/actions.js

@@ -2,7 +2,9 @@
  * Internal dependencies
  */
 import { LEGAL_REQUEST, LEGAL_SET, TOS_ACCEPT } from 'state/action-types';
+
 import 'state/data-layer/wpcom/legal';
+import 'state/legal/init';
 
 export const requestLegalData = () => ( {
 	type: LEGAL_REQUEST,

client/state/legal/init.js

@@ -0,0 +1,7 @@
+/**
+ * Internal dependencies
+ */
+import { registerReducer } from 'state/redux-store';
+import legalReducer from './reducer';
+
+registerReducer( [ 'legal' ], legalReducer );

client/state/legal/package.json

@@ -0,0 +1,5 @@
+{
+	"sideEffects": [
+		"./init.js"
+	]
+}

client/state/legal/reducer.js

@@ -2,5 +2,7 @@
  * Internal dependencies
  */
 import { LEGAL_SET } from 'state/action-types';
+import { withStorageKey } from 'state/utils';
 
-export default ( state = {}, { type, legalData } ) => ( type === LEGAL_SET ? legalData : state );
+const reducer = ( state = {}, { type, legalData } ) => ( type === LEGAL_SET ? legalData : state );
+export default withStorageKey( 'legal', reducer );

client/state/reducer.js

@@ -48,7 +48,6 @@ import jetpackProductInstall from './jetpack-product-install/reducer';
 import jetpackRemoteInstall from './jetpack-remote-install/reducer';
 import jetpackSync from './jetpack-sync/reducer';
 import jitm from './jitm/reducer';
-import legal from './legal/reducer';
 import media from './media/reducer';
 import memberships from './memberships/reducer';
 import mailchimp from './mailchimp/reducer';
@@ -124,7 +123,6 @@ const reducers = {
 	jetpackRemoteInstall,
 	jetpackSync,
 	jitm,
-	legal,
 	media,
 	memberships,
 	mySites,

client/state/selectors/should-display-tos-update-banner.js

@@ -1,3 +1,8 @@
+/**
+ * Internal dependencies
+ */
+import 'state/legal/init';
+
 /**
  * Indicates if a Terms or Service update banner should be displayed.
  *