[iOS] Upstream chrome commands

ios/chrome/browser/ui/commands/generic_chrome_command.mm

Index: ios/chrome/browser/ui/commands/generic_chrome_command.mm
diff --git a/ios/chrome/browser/ui/commands/generic_chrome_command.mm b/ios/chrome/browser/ui/commands/generic_chrome_command.mm
new file mode 100644
index 0000000000000000000000000000000000000000..bc737a6fef3f45bf5e3c891d4604d36cb9bb9985
--- /dev/null
+++ b/ios/chrome/browser/ui/commands/generic_chrome_command.mm
@@ -0,0 +1,36 @@
+// Copyright 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import "ios/chrome/browser/ui/commands/generic_chrome_command.h"
+
+#import <UIKit/UIKit.h>
+
+#include "base/logging.h"
+#import "ios/chrome/browser/ui/commands/UIKit+ChromeExecuteCommand.h"
+
+@implementation GenericChromeCommand {
+  NSInteger _tag;
+}
+
+@synthesize tag = _tag;
+
+- (instancetype)init {
+  return [self initWithTag:0];
+}
+
+- (instancetype)initWithTag:(NSInteger)tag {
+  self = [super init];
+  if (self) {
+    _tag = tag;
+  }
+  return self;
+}
+
+- (void)executeOnMainWindow {
+  UIWindow* mainWindow = [[UIApplication sharedApplication] keyWindow];
+  DCHECK(mainWindow);
+  [mainWindow chromeExecuteCommand:self];
+}
+
+@end