Use constants for Location and IAM module classes

Details:
* Use constants for the 2 class names for the Location and IAM modules that are used by NSClassFromString: `OneSignalLocationManager` and `OneSignalInAppMessages`
Motivation:
* These can be easily missed. When the class `OneSignalLocation` was renamed to `OneSignalLocationManager`, some of the hardcoded strings were missed in `NSClassFromString` calls.

Author: nan-li

iOS_SDK/OneSignalSDK/OneSignalCore/Source/OneSignalCommonDefines.h

@@ -118,6 +118,10 @@
 // can use them directly.
 #define DEFAULT_UNAUTHORIZATIONOPTIONS (UNAuthorizationOptionSound + UNAuthorizationOptionBadge + UNAuthorizationOptionAlert)
 
+// Class Names used with NSClassFromString
+#define ONE_SIGNAL_LOCATION_CLASS_NAME @"OneSignalLocationManager"
+#define ONE_SIGNAL_IN_APP_MESSAGES_CLASS_NAME @"OneSignalInAppMessages"
+
 // iOS Parameter Names
 #define IOS_FBA @"fba"
 #define IOS_USES_PROVISIONAL_AUTHORIZATION @"uses_provisional_auth"

iOS_SDK/OneSignalSDK/OneSignalInAppMessages/Model/OSInAppMessageLocationPrompt.m

@@ -52,7 +52,7 @@ - (void)handlePrompt:(void (^)(PromptActionResult result))completionHandler {
      This code calls [OneSignalLocation promptLocationFallbackToSettings:true completionHandler:completionHandler];
      */
     BOOL fallback = YES;
-    let oneSignalLocationManager = NSClassFromString(@"OneSignalLocationManager");
+    let oneSignalLocationManager = NSClassFromString(ONE_SIGNAL_LOCATION_CLASS_NAME);
     if (oneSignalLocationManager != nil && [oneSignalLocationManager respondsToSelector:@selector(promptLocationFallbackToSettings:completionHandler:)]) {
         NSMethodSignature* signature = [oneSignalLocationManager methodSignatureForSelector:@selector(promptLocationFallbackToSettings:completionHandler:)];
         NSInvocation* invocation = [NSInvocation invocationWithMethodSignature: signature];

iOS_SDK/OneSignalSDK/Source/OSMigrationController.m

@@ -41,7 +41,7 @@ @implementation OSMigrationController
 
 - (void)migrate {
     [self migrateToVersion_02_14_00_AndGreater];
-    let oneSignalInAppMessages = NSClassFromString(@"OneSignalInAppMessages");
+    let oneSignalInAppMessages = NSClassFromString(ONE_SIGNAL_IN_APP_MESSAGES_CLASS_NAME);
     if (oneSignalInAppMessages != nil && [oneSignalInAppMessages respondsToSelector:@selector(migrate)]) {
         [oneSignalInAppMessages performSelector:@selector(migrate)];
     }

iOS_SDK/OneSignalSDK/Source/OneSignal.m

@@ -208,7 +208,7 @@ + (void)logout {
 }
 
 + (Class<OSInAppMessages>)InAppMessages {
-    let oneSignalInAppMessages = NSClassFromString(@"OneSignalInAppMessages");
+    let oneSignalInAppMessages = NSClassFromString(ONE_SIGNAL_IN_APP_MESSAGES_CLASS_NAME);
     if (oneSignalInAppMessages != nil && [oneSignalInAppMessages respondsToSelector:@selector(InAppMessages)]) {
         return [oneSignalInAppMessages performSelector:@selector(InAppMessages)];
     } else {
@@ -222,7 +222,7 @@ + (void)logout {
 }
 
 + (Class<OSLocation>)Location {
-    let oneSignalLocationManager = NSClassFromString(@"OneSignalLocationManager");
+    let oneSignalLocationManager = NSClassFromString(ONE_SIGNAL_LOCATION_CLASS_NAME);
     if (oneSignalLocationManager != nil && [oneSignalLocationManager respondsToSelector:@selector(Location)]) {
         return [oneSignalLocationManager performSelector:@selector(Location)];
     } else {
@@ -380,7 +380,7 @@ + (void)startNewSessionInternal {
     [OneSignalTrackFirebaseAnalytics trackInfluenceOpenEvent];
 
     // Clear last location after attaching data to user state or not
-    let oneSignalLocation = NSClassFromString(@"OneSignalLocation");
+    let oneSignalLocation = NSClassFromString(ONE_SIGNAL_LOCATION_CLASS_NAME);
     if (oneSignalLocation != nil && [oneSignalLocation respondsToSelector:@selector(clearLastLocation)]) {
         [oneSignalLocation performSelector:@selector(clearLastLocation)];
     }
@@ -394,7 +394,7 @@ + (void)startNewSessionInternal {
     // The OSMessagingController is an OSPushSubscriptionObserver so that we pull IAMs once we have the sub id
     NSString *subscriptionId = OneSignalUserManagerImpl.sharedInstance.pushSubscriptionId;
     if (subscriptionId) {
-        let oneSignalInAppMessages = NSClassFromString(@"OneSignalInAppMessages");
+        let oneSignalInAppMessages = NSClassFromString(ONE_SIGNAL_IN_APP_MESSAGES_CLASS_NAME);
         if (oneSignalInAppMessages != nil && [oneSignalInAppMessages respondsToSelector:@selector(getInAppMessagesFromServer:)]) {
             [oneSignalInAppMessages performSelector:@selector(getInAppMessagesFromServer:) withObject:subscriptionId];
         }
@@ -414,7 +414,7 @@ + (void)startNewSessionInternal {
 }
 
 + (void)startInAppMessages {
-    let oneSignalInAppMessages = NSClassFromString(@"OneSignalInAppMessages");
+    let oneSignalInAppMessages = NSClassFromString(ONE_SIGNAL_IN_APP_MESSAGES_CLASS_NAME);
     if (oneSignalInAppMessages != nil && [oneSignalInAppMessages respondsToSelector:@selector(start)]) {
         [oneSignalInAppMessages performSelector:@selector(start)];
     }
@@ -426,7 +426,7 @@ + (void)startOutcomes {
 }
 
 + (void)startLocation {
-    let oneSignalLocation = NSClassFromString(@"OneSignalLocation");
+    let oneSignalLocation = NSClassFromString(ONE_SIGNAL_LOCATION_CLASS_NAME);
     if (oneSignalLocation != nil && [oneSignalLocation respondsToSelector:@selector(start)]) {
         [oneSignalLocation performSelector:@selector(start)];
     }
@@ -619,7 +619,7 @@ + (void)downloadIOSParamsWithAppId:(NSString *)appId {
         [[OSRemoteParamController sharedController] saveRemoteParams:result];
         if ([[OSRemoteParamController sharedController] hasLocationKey]) {
             BOOL shared = [result[IOS_LOCATION_SHARED] boolValue];
-            let oneSignalLocation = NSClassFromString(@"OneSignalLocation");
+            let oneSignalLocation = NSClassFromString(ONE_SIGNAL_LOCATION_CLASS_NAME);
             if (oneSignalLocation != nil && [oneSignalLocation respondsToSelector:@selector(startLocationSharedWithFlag:)]) {
                 [OneSignalCoreHelper callSelector:@selector(startLocationSharedWithFlag:) onObject:oneSignalLocation withArg:shared];
             }

iOS_SDK/OneSignalSDK/Source/OneSignalLifecycleObserver.m

@@ -81,11 +81,11 @@ - (void)didBecomeActive {
 
     if ([OneSignalConfigManager getAppId]) {
         [OneSignalTracker onFocus:NO];
-        let oneSignalLocation = NSClassFromString(@"OneSignalLocation");
+        let oneSignalLocation = NSClassFromString(ONE_SIGNAL_LOCATION_CLASS_NAME);
         if (oneSignalLocation != nil && [oneSignalLocation respondsToSelector:@selector(onFocus:)]) {
             [OneSignalCoreHelper callSelector:@selector(onFocus:) onObject:oneSignalLocation withArg:YES];
         }
-        let oneSignalInAppMessages = NSClassFromString(@"OneSignalInAppMessages");
+        let oneSignalInAppMessages = NSClassFromString(ONE_SIGNAL_IN_APP_MESSAGES_CLASS_NAME);
         if (oneSignalInAppMessages != nil && [oneSignalInAppMessages respondsToSelector:@selector(onApplicationDidBecomeActive)]) {
             [oneSignalInAppMessages performSelector:@selector(onApplicationDidBecomeActive)];
         }
@@ -105,7 +105,7 @@ - (void)willResignActive {
 - (void)didEnterBackground {
     [OneSignalLog onesignalLog:ONE_S_LL_VERBOSE message:@"application/scene didEnterBackground"];
     if ([OneSignalConfigManager getAppId]) {
-        let oneSignalLocation = NSClassFromString(@"OneSignalLocation");
+        let oneSignalLocation = NSClassFromString(ONE_SIGNAL_LOCATION_CLASS_NAME);
         if (oneSignalLocation != nil && [oneSignalLocation respondsToSelector:@selector(onFocus:)]) {
             [OneSignalCoreHelper callSelector:@selector(onFocus:) onObject:oneSignalLocation withArg:NO];
         }