chore: import upstream snapshot with attribution

tensorflow/lite/delegates/gpu/metal/host.m

@@ -0,0 +1,53 @@
+/* Copyright 2019 The TensorFlow Authors. All Rights Reserved.
+
+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.
+==============================================================================*/
+
+// This is a shell app used for hosting the unittests. This way any real app
+// startup code doesn't get in the way when running unittests.
+#import <UIKit/UIKit.h>
+
+@interface AppDelegate : UIResponder <UIApplicationDelegate>
+@end
+
+@interface AppDelegate ()
+@end
+
+@implementation AppDelegate
+
+- (BOOL)application:(UIApplication *)application
+    didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
+  return YES;
+}
+
+- (void)applicationWillResignActive:(UIApplication *)application {
+}
+
+- (void)applicationDidEnterBackground:(UIApplication *)application {
+}
+
+- (void)applicationWillEnterForeground:(UIApplication *)application {
+}
+
+- (void)applicationDidBecomeActive:(UIApplication *)application {
+}
+
+- (void)applicationWillTerminate:(UIApplication *)application {
+}
+@end
+
+int main(int argc, char *argv[]) {
+  @autoreleasepool {
+    return UIApplicationMain(argc, argv, nil, @"AppDelegate");
+  }
+}