add response type "arraybuffer" support for iOS

src/ios/AFNetworking/AFURLResponseSerialization.h

@@ -308,4 +308,11 @@ FOUNDATION_EXPORT NSString * const AFNetworkingOperationFailingURLResponseErrorK
 
 FOUNDATION_EXPORT NSString * const AFNetworkingOperationFailingURLResponseDataErrorKey;
 
+/**
+`AFNetworkingOperationFailingURLResponseBodyErrorKey`
+The corresponding value is an `NSString` containing the decoded error message.
+ */
+
+FOUNDATION_EXPORT NSString * const AFNetworkingOperationFailingURLResponseBodyErrorKey;
+
 NS_ASSUME_NONNULL_END

src/ios/AFNetworking/AFURLResponseSerialization.m

@@ -34,6 +34,7 @@
 NSString * const AFURLResponseSerializationErrorDomain = @"com.alamofire.error.serialization.response";
 NSString * const AFNetworkingOperationFailingURLResponseErrorKey = @"com.alamofire.serialization.response.error.response";
 NSString * const AFNetworkingOperationFailingURLResponseDataErrorKey = @"com.alamofire.serialization.response.error.data";
+NSString * const AFNetworkingOperationFailingURLResponseBodyErrorKey = @"com.alamofire.serialization.response.error.body";
 
 static NSError * AFErrorWithUnderlyingError(NSError *error, NSError *underlyingError) {
     if (!error) {
@@ -525,7 +526,7 @@ static NSLock* imageLock = nil;
     dispatch_once(&onceToken, ^{
         imageLock = [[NSLock alloc] init];
     });
-    
+
     [imageLock lock];
     image = [UIImage imageWithData:data];
     [imageLock unlock];
@@ -539,7 +540,7 @@ static UIImage * AFImageWithDataAtScale(NSData *data, CGFloat scale) {
     if (image.images) {
         return image;
     }
-    
+
     return [[UIImage alloc] initWithCGImage:[image CGImage] scale:scale orientation:image.imageOrientation];
 }