Address PR comments

Author: juan-arias

IdentityCore/src/MSIDBasicContext.h

@@ -32,7 +32,7 @@ NS_ASSUME_NONNULL_BEGIN
 @property (nonatomic, nullable) NSString *logComponent;
 @property (nonatomic, nullable) NSString *telemetryRequestId;
 @property (nonatomic, nullable) NSDictionary *appRequestMetadata;
-@property (nonatomic, readwrite) BOOL disableFRT;
+@property (nonatomic) BOOL disableFRT;
 
 @end
 

IdentityCore/src/oauth2/token/MSIDFamilyRefreshToken.h

@@ -26,9 +26,6 @@
 #import "MSIDRefreshToken.h"
 
 @interface MSIDFamilyRefreshToken : MSIDRefreshToken
-{
-    
-}
 
 - (instancetype)initWithRefreshToken:(MSIDRefreshToken *)refreshToken;
 

IdentityCore/src/requests/MSIDInteractiveAuthorizationCodeRequest.m

@@ -154,6 +154,8 @@ - (void)showWebComponentWithCompletion:(MSIDWebviewAuthCompletionHandler)complet
 - (void)updateCustomHeadersForFRTSupportIfNeeded
 {
     // This is meant to be implemented by subclasses
+    NSAssert(NO, @"Abstract method.");
+    return;
 }
 
 #pragma mark - v2 code