Check for signalContact vs. AB setup.

Same intent as previous check but more to the point, and doesn't
require tracking additional state.

// FREEBIE

Signal/src/contact/OWSContactsManager.h

@@ -45,6 +45,8 @@ extern NSString *const OWSContactsManagerSignalAccountsDidChangeNotification;
 // TODO: Remove this method.
 - (NSArray<Contact *> *)signalContacts;
 
+#pragma mark - Util
+
 - (NSString *)displayNameForPhoneIdentifier:(nullable NSString *)identifier;
 - (NSString *)displayNameForContact:(Contact *)contact;
 - (NSString *)displayNameForSignalAccount:(SignalAccount *)signalAccount;
@@ -53,9 +55,6 @@ extern NSString *const OWSContactsManagerSignalAccountsDidChangeNotification;
 - (NSAttributedString *)formattedFullNameForContact:(Contact *)contact font:(UIFont *)font;
 - (NSAttributedString *)formattedFullNameForRecipientId:(NSString *)recipientId font:(UIFont *)font;
 
-// TODO migrate to CNContact?
-- (BOOL)hasAddressBook;
-
 + (NSComparator _Nonnull)contactComparator;
 
 @end

Signal/src/contact/OWSContactsManager.m

@@ -448,11 +448,6 @@ NSString *const OWSContactsManagerSignalAccountsDidChangeNotification =
     return contact.image;
 }
 
-- (BOOL)hasAddressBook
-{
-    return (BOOL)self.addressBookReference;
-}
-
 #pragma mark - Logging
 
 + (NSString *)tag

Signal/src/util/OWSContactsSyncing.m

@@ -119,9 +119,9 @@ NSString *const kTSStorageManagerOWSContactsSyncingLastMessageKey =
 - (void)sendSyncContactsMessageIfPossible
 {
     AssertIsOnMainThread();
-
-    if (![self.contactsManager hasAddressBook]) {
-        // Don't bother until the contacts manager has finished setup.
+    if (self.contactsManager.signalContacts.count == 0) {
+        // Don't bother if the contacts manager has no contacts,
+        // e.g. if the contacts manager hasn't finished setup.
         return;
     }