user [nfc]: Clear out pre-7.0 backwards-compat code for display email

We refuse to connect to servers older than 7.0; see the README and
kMinSupportedZulipVersion.

Author: chrisbobbe

lib/api/model/initial_snapshot.dart

@@ -24,16 +24,6 @@ class InitialSnapshot {
 
   final List<CustomProfileField> customProfileFields;
 
-  /// The realm-level policy, on pre-FL 163 servers, for visibility of real email addresses.
-  ///
-  /// Search for "email_address_visibility" in https://zulip.com/api/register-queue.
-  ///
-  /// This field is removed in Zulip 7.0 (FL 163) and replaced with a user-level
-  /// setting:
-  ///   * https://zulip.com/api/update-settings#parameter-email_address_visibility
-  ///   * https://zulip.com/api/update-realm-user-settings-defaults#parameter-email_address_visibility
-  final EmailAddressVisibility? emailAddressVisibility; // TODO(server-7): remove
-
   final int serverPresencePingIntervalSeconds;
   final int serverPresenceOfflineThresholdSeconds;
 
@@ -146,7 +136,6 @@ class InitialSnapshot {
     required this.zulipMergeBase,
     required this.alertWords,
     required this.customProfileFields,
-    required this.emailAddressVisibility,
     required this.serverPresencePingIntervalSeconds,
     required this.serverPresenceOfflineThresholdSeconds,
     required this.serverTypingStartedExpiryPeriodMilliseconds,
@@ -185,14 +174,6 @@ class InitialSnapshot {
   Map<String, dynamic> toJson() => _$InitialSnapshotToJson(this);
 }
 
-enum EmailAddressVisibility {
-  @JsonValue(1) everyone,
-  @JsonValue(2) members,
-  @JsonValue(3) admins,
-  @JsonValue(4) nobody,
-  @JsonValue(5) moderators,
-}
-
 @JsonEnum(valueField: 'apiValue')
 enum RealmWildcardMentionPolicy {
   everyone(apiValue: 1),

lib/api/model/initial_snapshot.g.dart

@@ -51,8 +51,6 @@ mixin RealmStore on PerAccountStoreBase {
 
   RealmWildcardMentionPolicy get realmWildcardMentionPolicy; // TODO(#662): replaced by can_mention_many_users_group
 
-  EmailAddressVisibility? get emailAddressVisibility; // TODO: replaced at FL-163 by a user setting
-
   //|//////////////////////////////
   // Realm settings that lack events.
   // (Each of these is probably secretly a server setting.)
@@ -149,8 +147,6 @@ mixin ProxyRealmStore on RealmStore {
   @override
   RealmWildcardMentionPolicy get realmWildcardMentionPolicy => realmStore.realmWildcardMentionPolicy;
   @override
-  EmailAddressVisibility? get emailAddressVisibility => realmStore.emailAddressVisibility;
-  @override
   String get realmEmptyTopicDisplayName => realmStore.realmEmptyTopicDisplayName;
   @override
   Map<String, RealmDefaultExternalAccount> get realmDefaultExternalAccounts => realmStore.realmDefaultExternalAccounts;
@@ -187,7 +183,6 @@ class RealmStoreImpl extends PerAccountStoreBase with RealmStore {
     realmPresenceDisabled = initialSnapshot.realmPresenceDisabled,
     realmWaitingPeriodThreshold = initialSnapshot.realmWaitingPeriodThreshold,
     realmWildcardMentionPolicy = initialSnapshot.realmWildcardMentionPolicy,
-    emailAddressVisibility = initialSnapshot.emailAddressVisibility,
     _realmEmptyTopicDisplayName = initialSnapshot.realmEmptyTopicDisplayName,
     realmDefaultExternalAccounts = initialSnapshot.realmDefaultExternalAccounts,
     customProfileFields = _sortCustomProfileFields(initialSnapshot.customProfileFields);
@@ -220,9 +215,6 @@ class RealmStoreImpl extends PerAccountStoreBase with RealmStore {
   @override
   final RealmWildcardMentionPolicy realmWildcardMentionPolicy;
 
-  @override
-  final EmailAddressVisibility? emailAddressVisibility;
-
   @override
   String get realmEmptyTopicDisplayName {
     assert(zulipFeatureLevel >= 334); // TODO(server-10)

lib/model/realm.dart

@@ -95,31 +95,7 @@ mixin UserStore on PerAccountStoreBase, RealmStore {
   ///
   /// Returns null if self-user isn't able to see the user's real email address,
   /// or if the user isn't actually a user we know about.
-  String? userDisplayEmail(int userId) {
-    final user = getUser(userId);
-    if (user == null) return null;
-    if (zulipFeatureLevel >= 163) { // TODO(server-7)
-      // A non-null value means self-user has access to [user]'s real email,
-      // while a null value means it doesn't have access to the email.
-      // Search for "delivery_email" in https://zulip.com/api/register-queue.
-      return user.deliveryEmail;
-    } else {
-      if (user.deliveryEmail != null) {
-        // A non-null value means self-user has access to [user]'s real email,
-        // while a null value doesn't necessarily mean it doesn't have access
-        // to the email, ....
-        return user.deliveryEmail;
-      } else if (emailAddressVisibility == EmailAddressVisibility.everyone) {
-        // ... we have to also check for [PerAccountStore.emailAddressVisibility].
-        // See:
-        //   * https://github.com/zulip/zulip-mobile/pull/5515#discussion_r997731727
-        //   * https://chat.zulip.org/#narrow/stream/378-api-design/topic/email.20address.20visibility/near/1296133
-        return user.email;
-      } else {
-        return null;
-      }
-    }
-  }
+  String? userDisplayEmail(int userId) => getUser(userId)?.deliveryEmail;
 
   /// Whether [user] has passed the realm's waiting period to be a full member.
   ///

lib/model/user.dart

@@ -251,7 +251,7 @@ int _lastEmailSuffix = 1000;
 /// other data in the test, or if the IDs need to increase in a different order
 /// from the calls to [user].
 ///
-/// If `email` is not given, it defaults to `deliveryEmail` if given,
+/// If `email` is not given, it defaults to `deliveryEmail` if given and non-null,
 /// or else to a value resembling the Zulip server's generated fake emails.
 User user({
   int? userId,
@@ -1202,7 +1202,6 @@ InitialSnapshot initialSnapshot({
   String? zulipMergeBase,
   List<String>? alertWords,
   List<CustomProfileField>? customProfileFields,
-  EmailAddressVisibility? emailAddressVisibility,
   int? serverPresencePingIntervalSeconds,
   int? serverPresenceOfflineThresholdSeconds,
   int? serverTypingStartedExpiryPeriodMilliseconds,
@@ -1242,7 +1241,6 @@ InitialSnapshot initialSnapshot({
     zulipMergeBase: zulipMergeBase ?? recentZulipVersion,
     alertWords: alertWords ?? ['klaxon'],
     customProfileFields: customProfileFields ?? [],
-    emailAddressVisibility: emailAddressVisibility ?? EmailAddressVisibility.everyone,
     serverPresencePingIntervalSeconds: serverPresencePingIntervalSeconds ?? 60,
     serverPresenceOfflineThresholdSeconds: serverPresenceOfflineThresholdSeconds ?? 140,
     serverTypingStartedExpiryPeriodMilliseconds: