Block calls to get config until DB load completes (#7975)

* Block calls to get config until DB load completes

* Add changelog

* Add TODO for refactoring

Author: karenyz

FirebaseRemoteConfig/CHANGELOG.md

@@ -1,5 +1,6 @@
 # Unreleased
 - [fixed] Fixed throttling issue when fetch fails due to no network. (#6628)
+- [fixed] Fixed issue where sometimes the local config returned is empty. (#7424)
 
 # v7.10.0
 - [changed] Throw exception if projectID is missing from FirebaseOptions. (#7725)

FirebaseRemoteConfig/Sources/RCNConfigContent.m

@@ -86,8 +86,7 @@ - (instancetype)initWithDBManager:(RCNConfigDBManager *)DBManager {
       _bundleIdentifier = @"";
     }
     _DBManager = DBManager;
-    // Waits for both config and Personalization data to load.
-    _configLoadFromDBSemaphore = dispatch_semaphore_create(1);
+    _configLoadFromDBSemaphore = dispatch_semaphore_create(0);
     [self loadConfigFromMainTable];
   }
   return self;
@@ -123,12 +122,12 @@ - (void)loadConfigFromMainTable {
                    dispatch_semaphore_signal(self->_configLoadFromDBSemaphore);
                  }];
 
+  // TODO(karenzeng): Refactor personalization to be returned in loadMainWithBundleIdentifier above
   [_DBManager loadPersonalizationWithCompletionHandler:^(
                   BOOL success, NSDictionary *fetchedPersonalization,
                   NSDictionary *activePersonalization, NSDictionary *defaultConfig) {
     self->_fetchedPersonalization = [fetchedPersonalization copy];
     self->_activePersonalization = [activePersonalization copy];
-    dispatch_semaphore_signal(self->_configLoadFromDBSemaphore);
   }];
 }