Fix init in DBTransportBaseHostnameConfig (#383)

* fix init in DBTransportBaseHostnameConfig

* fix downloadContent setting

* add comment to initializer

Author: jamesyangf

Source/ObjectiveDropboxOfficial/Shared/Handwritten/Networking/DBTransportBaseHostnameConfig.h

@@ -40,6 +40,18 @@ NS_ASSUME_NONNULL_BEGIN
 ///
 - (instancetype)init;
 
+///
+/// Constructor that takes in a set of custom hostnames to use for api calls.
+///
+/// @param meta the hostname to metaserver
+/// @param api the hostname to api server
+/// @param content the hostname to content server
+/// @param notify the hostname to notify server
+///
+/// @return An initialized instance with the provided hostname configuration
+///
+- (instancetype)initWithMeta:(NSString *)meta api:(NSString *)api content:(NSString *)content notify:(NSString *)notify;
+
 ///
 /// Constructor that takes in a set of custom hostnames to use for api calls.
 ///
@@ -51,7 +63,7 @@ NS_ASSUME_NONNULL_BEGIN
 ///
 /// @return An initialized instance with the provided hostname configuration
 ///
-- (instancetype)initWithMeta:(NSString *)meta api:(NSString *)api content:(NSString *)content downloadContent:(NSString *)downloadContent notify:(NSString *)notify;
+- (instancetype)initWithMeta:(NSString *)meta api:(NSString *)api content:(NSString *)content downloadContent:(NSString *)downloadContent notify:(NSString *)notify NS_DESIGNATED_INITIALIZER;
 
 ///
 /// Returns the prefix to use for API calls to the given route type.

Source/ObjectiveDropboxOfficial/Shared/Handwritten/Networking/DBTransportBaseHostnameConfig.m

@@ -37,23 +37,21 @@ - (instancetype)initWithMeta:(NSString *)meta
                          api:(NSString *)api
                      content:(NSString *)content
                       notify:(NSString *)notify {
-  if (self = [super init]) {
-    _meta = meta;
-    _api = api;
-    _content = content;
-    _downloadContent = content;
-    _notify = notify;
-  }
-  return self;
+    return [self initWithMeta:meta api:api content:content downloadContent:content notify:notify];
 }
 
 - (instancetype)initWithMeta:(NSString *)meta
                          api:(NSString *)api
                      content:(NSString *)content
              downloadContent:(NSString *)downloadContent
                       notify:(NSString *)notify {
-  self = [self initWithMeta:meta api:api content:content notify:notify];
-  _downloadContent = downloadContent;
+  if (self = [super init]) {
+    _meta = meta;
+    _api = api;
+    _content = content;
+    _downloadContent = downloadContent;
+    _notify = notify;
+  }
   return self;
 }