Replacing FIR_SWIFT_NAME macro with NS_SWIFT_NAME. (#476)

* Replacing FIR_SWIFT_NAME macro with NS_SWIFT_NAME.

This pushes the minimum Xcode version to 7.3, as NS_SWIFT_NAME was
limited before that version (which is why the macro was introduced in
the first place).

* Fixed FIRMessaging header

9 files changed, 12 insertions, 50 deletions

diff --git a/Firebase/Database/Public/FIRDataEventType.h b/Firebase/Database/Public/FIRDataEventType.h
index fccc98a..916ce32 100644
--- a/Firebase/Database/Public/FIRDataEventType.h
+++ b/Firebase/Database/Public/FIRDataEventType.h
@@ -18,7 +18,6 @@
 #define Firebase_FIRDataEventType_h
 
 #import <Foundation/Foundation.h>
-#import "FIRDatabaseSwiftNameSupport.h"
 
 /**
  * This enum is the set of events that you can observe at a Firebase Database location.
@@ -34,6 +33,6 @@ typedef NS_ENUM(NSInteger, FIRDataEventType) {
     FIRDataEventTypeChildMoved,
     /// Any data changes at a location or, recursively, at any child node.
     FIRDataEventTypeValue
-} FIR_SWIFT_NAME(DataEventType);
+} NS_SWIFT_NAME(DataEventType);
 
 #endif
diff --git a/Firebase/Database/Public/FIRDataSnapshot.h b/Firebase/Database/Public/FIRDataSnapshot.h
index e465045..02a1e6a 100644
--- a/Firebase/Database/Public/FIRDataSnapshot.h
+++ b/Firebase/Database/Public/FIRDataSnapshot.h
@@ -15,7 +15,6 @@
  */
 
 #import <Foundation/Foundation.h>
-#import "FIRDatabaseSwiftNameSupport.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -30,7 +29,7 @@ NS_ASSUME_NONNULL_BEGIN
  * They can't be modified and will never change. To modify data at a location,
  * use a FIRDatabaseReference (e.g. with setValue:).
  */
-FIR_SWIFT_NAME(DataSnapshot)
+NS_SWIFT_NAME(DataSnapshot)
 @interface FIRDataSnapshot : NSObject
 
 
diff --git a/Firebase/Database/Public/FIRDatabase.h b/Firebase/Database/Public/FIRDatabase.h
index 606f164..6761669 100644
--- a/Firebase/Database/Public/FIRDatabase.h
+++ b/Firebase/Database/Public/FIRDatabase.h
@@ -16,7 +16,6 @@
 
 #import <Foundation/Foundation.h>
 #import "FIRDatabaseReference.h"
-#import "FIRDatabaseSwiftNameSupport.h"
 
 @class FIRApp;
 
@@ -27,7 +26,7 @@ NS_ASSUME_NONNULL_BEGIN
  * [FIRDatabase database]. To access a location in the database and read or write data,
  * use [FIRDatabase reference].
  */
-FIR_SWIFT_NAME(Database)
+NS_SWIFT_NAME(Database)
 @interface FIRDatabase : NSObject
 
 /**
@@ -43,7 +42,7 @@ FIR_SWIFT_NAME(Database)
  *
  * @return A FIRDatabase instance.
  */
-+ (FIRDatabase *) database FIR_SWIFT_NAME(database());
++ (FIRDatabase *) database NS_SWIFT_NAME(database());
 
 /**
  * Gets a FirebaseDatabase instance for the specified URL.
@@ -72,7 +71,7 @@ FIR_SWIFT_NAME(Database)
  * @param app The FIRApp to get a FIRDatabase for.
  * @return A FIRDatabase instance.
  */
-+ (FIRDatabase *) databaseForApp:(FIRApp *)app FIR_SWIFT_NAME(database(app:));
++ (FIRDatabase *) databaseForApp:(FIRApp *)app NS_SWIFT_NAME(database(app:));
 
 /** The FIRApp instance to which this FIRDatabase belongs. */
 @property (weak, readonly, nonatomic) FIRApp *app;
@@ -134,7 +133,7 @@ FIR_SWIFT_NAME(Database)
  * application.
  *
  */
-@property (nonatomic) BOOL persistenceEnabled FIR_SWIFT_NAME(isPersistenceEnabled);
+@property (nonatomic) BOOL persistenceEnabled NS_SWIFT_NAME(isPersistenceEnabled);
 
 /**
  * By default the Firebase Database client will use up to 10MB of disk space to cache data. If the cache grows beyond
diff --git a/Firebase/Database/Public/FIRDatabaseQuery.h b/Firebase/Database/Public/FIRDatabaseQuery.h
index be4ad27..ef56643 100644
--- a/Firebase/Database/Public/FIRDatabaseQuery.h
+++ b/Firebase/Database/Public/FIRDatabaseQuery.h
@@ -15,7 +15,6 @@
  */
 
 #import <Foundation/Foundation.h>
-#import "FIRDatabaseSwiftNameSupport.h"
 #import "FIRDataEventType.h"
 #import "FIRDataSnapshot.h"
 
@@ -26,7 +25,7 @@ NS_ASSUME_NONNULL_BEGIN
  * are returned by observeEventType: and and can later be passed to removeObserverWithHandle: to
  * stop receiving updates.
  */
-typedef NSUInteger FIRDatabaseHandle FIR_SWIFT_NAME(DatabaseHandle);
+typedef NSUInteger FIRDatabaseHandle NS_SWIFT_NAME(DatabaseHandle);
 
 /**
  * A FIRDatabaseQuery instance represents a query over the data at a particular location.
@@ -35,7 +34,7 @@ typedef NSUInteger FIRDatabaseHandle FIR_SWIFT_NAME(DatabaseHandle);
  * on a FIRDatabaseReference. The query methods can be chained to further specify the data you are interested in
  * observing
  */
-FIR_SWIFT_NAME(DatabaseQuery)
+NS_SWIFT_NAME(DatabaseQuery)
 @interface FIRDatabaseQuery : NSObject
 
 
diff --git a/Firebase/Database/Public/FIRDatabaseReference.h b/Firebase/Database/Public/FIRDatabaseReference.h
index 53d0cdd..fdc92b6 100644
--- a/Firebase/Database/Public/FIRDatabaseReference.h
+++ b/Firebase/Database/Public/FIRDatabaseReference.h
@@ -17,7 +17,6 @@
 #import <Foundation/Foundation.h>
 #import "FIRDatabaseQuery.h"
 #import "FIRDatabase.h"
-#import "FIRDatabaseSwiftNameSupport.h"
 #import "FIRDataSnapshot.h"
 #import "FIRMutableData.h"
 #import "FIRTransactionResult.h"
@@ -36,7 +35,7 @@ NS_ASSUME_NONNULL_BEGIN
  * to read data (ie. observeEventType:withBlock:), write data (ie. setValue:), and to
  * create new FIRDatabaseReferences (ie. child:).
  */
-FIR_SWIFT_NAME(DatabaseReference)
+NS_SWIFT_NAME(DatabaseReference)
 @interface FIRDatabaseReference : FIRDatabaseQuery
 
 
diff --git a/Firebase/Database/Public/FIRDatabaseSwiftNameSupport.h b/Firebase/Database/Public/FIRDatabaseSwiftNameSupport.h
deleted file mode 100644
index 55e1bcc..0000000
--- a/Firebase/Database/Public/FIRDatabaseSwiftNameSupport.h
+++ /dev/null
@@ -1,29 +0,0 @@
-/*
- * Copyright 2017 Google
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#ifndef FIR_SWIFT_NAME
-
-#import <Foundation/Foundation.h>
-
-// NS_SWIFT_NAME can only translate factory methods before the iOS 9.3 SDK.
-// Wrap it in our own macro if it's a non-compatible SDK.
-#ifdef __IPHONE_9_3
-#define FIR_SWIFT_NAME(X) NS_SWIFT_NAME(X)
-#else
-#define FIR_SWIFT_NAME(X)  // Intentionally blank.
-#endif  // #ifdef __IPHONE_9_3
-
-#endif  // FIR_SWIFT_NAME
diff --git a/Firebase/Database/Public/FIRMutableData.h b/Firebase/Database/Public/FIRMutableData.h
index 4e7250a..7445d71 100644
--- a/Firebase/Database/Public/FIRMutableData.h
+++ b/Firebase/Database/Public/FIRMutableData.h
@@ -15,7 +15,6 @@
  */
 
 #import <Foundation/Foundation.h>
-#import "FIRDatabaseSwiftNameSupport.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -35,7 +34,7 @@ NS_ASSUME_NONNULL_BEGIN
  *
  * Note that changes made to a child FIRMutableData instance will be visible to the parent.
  */
-FIR_SWIFT_NAME(MutableData)
+NS_SWIFT_NAME(MutableData)
 @interface FIRMutableData : NSObject
 
 
diff --git a/Firebase/Database/Public/FIRServerValue.h b/Firebase/Database/Public/FIRServerValue.h
index f5eadd5..365590c 100644
--- a/Firebase/Database/Public/FIRServerValue.h
+++ b/Firebase/Database/Public/FIRServerValue.h
@@ -14,15 +14,13 @@
  * limitations under the License.
  */
 
-#import "FIRDatabaseSwiftNameSupport.h"
-
 NS_ASSUME_NONNULL_BEGIN
 
 /**
  * Placeholder values you may write into Firebase Database as a value or priority
  * that will automatically be populated by the Firebase Database server.
  */
-FIR_SWIFT_NAME(ServerValue)
+NS_SWIFT_NAME(ServerValue)
 @interface FIRServerValue : NSObject
 
 /**
diff --git a/Firebase/Database/Public/FIRTransactionResult.h b/Firebase/Database/Public/FIRTransactionResult.h
index 3c2d39a..d356c5c 100644
--- a/Firebase/Database/Public/FIRTransactionResult.h
+++ b/Firebase/Database/Public/FIRTransactionResult.h
@@ -15,7 +15,6 @@
  */
 
 #import <Foundation/Foundation.h>
-#import "FIRDatabaseSwiftNameSupport.h"
 #import "FIRMutableData.h"
 
 NS_ASSUME_NONNULL_BEGIN
@@ -23,7 +22,7 @@ NS_ASSUME_NONNULL_BEGIN
 /**
  * Used for runTransactionBlock:. An FIRTransactionResult instance is a container for the results of the transaction.
  */
-FIR_SWIFT_NAME(TransactionResult)
+NS_SWIFT_NAME(TransactionResult)
 @interface FIRTransactionResult : NSObject
 
 /**