[ios] Adds code for Omaha and the upgrade center.

ios/chrome/browser/upgrade/upgrade_center.h

Index: ios/chrome/browser/upgrade/upgrade_center.h
diff --git a/ios/chrome/browser/upgrade/upgrade_center.h b/ios/chrome/browser/upgrade/upgrade_center.h
new file mode 100644
index 0000000000000000000000000000000000000000..a9ee57fc20421d2ea147d2c6f44977ea2a8cc543
--- /dev/null
+++ b/ios/chrome/browser/upgrade/upgrade_center.h
@@ -0,0 +1,62 @@
+// Copyright (c) 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.
+
+#ifndef IOS_CHROME_BROWSER_UPGRADE_UPGRADE_CENTER_H_
+#define IOS_CHROME_BROWSER_UPGRADE_UPGRADE_CENTER_H_
+
+#import <UIKit/UIKit.h>
+
+#include "ios/chrome/browser/upgrade/upgrade_recommended_details.h"
+
+@class UpgradeCenter;
+
+namespace infobars {
+class InfoBarManager;
+}
+
+@protocol UpgradeCenterClientProtocol
+
+// This is expected to call -addInfoBarToHelper:forTabId: for each tab to place
+// the infobars in the UI. The client must not unregister itself while in this
+// method.
+- (void)showUpgrade:(UpgradeCenter*)center;
+
+@end
+
+@interface UpgradeCenter : NSObject
+
+// Returns the singleton instance of the class.
++ (UpgradeCenter*)sharedInstance;
+
+// Registers a client for the UpgradeCenter. The clients are not retained,
+// unregisterClient: must be called before the object goes away.
+- (void)registerClient:(id<UpgradeCenterClientProtocol>)client;
+
+// Unregisters a client.
+- (void)unregisterClient:(id<UpgradeCenterClientProtocol>)client;
+
+// Clients should call this method when -showUpgrade: is called or when a new
+// tab is created. The infobar will not be created if it already exists or if
+// there is no need to do so.
+- (void)addInfoBarToManager:(infobars::InfoBarManager*)infoBarManager
+                   forTabId:(NSString*)tabId;
+
+// For the UpgradeCenter to make the distinction between an infobar closed by
+// the user directly and an infobar dismissed because the Tab it is on is
+// removed.
+- (void)tabWillClose:(NSString*)tabId;
+
+// Called when a notification is received from one of the upgrade mechanism.
+- (void)upgradeNotificationDidOccur:(const UpgradeRecommendedDetails&)details;
+
+@end
+
+@interface UpgradeCenter (UsedForTests)
+// Reset everything (forget clients, remove the infobar everywhere...)
+- (void)resetForTests;
+// Simulate the minimum display interval having elapsed.
+- (void)setLastDisplayToPast;
+@end
+
+#endif  // IOS_CHROME_BROWSER_UPGRADE_UPGRADE_CENTER_H_