[Clean Skeleton] Migrate code to clean/

ios/chrome/app/application_state.h

-// Copyright 2016 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.
-
-// ======                        New Architecture                         =====
-// =         This code is only used in the new iOS Chrome architecture.       =
-// ============================================================================
-
-#ifndef IOS_CHROME_APP_APPLICATION_STATE_H_
-#define IOS_CHROME_APP_APPLICATION_STATE_H_
-
-#import <UIKit/UIKit.h>
-
-#import "ios/chrome/app/application_phase.h"
-
-namespace base {
-class SupportsUserData;
-}
-
-namespace ios {
-class ChromeBrowserState;
-}
-
-@protocol ApplicationStep;
-@protocol URLOpening;
-
-typedef NSMutableArray<id<ApplicationStep>> ApplicationStepArray;
-
-// An ApplicationState object stores information about Chrome's status in the
-// iOS application lifecycle and owns root-level global objects needed
-// throughout the app (specifically, |browserState| and |window|).
-// Additionally, an ApplicationState object keeps arrays of steps to perform
-// in response to various changes in the overall application states.
-// These steps are grouped into launch (used when the app is cold starting),
-// termination (used when the app is shutting down), background (used when the
-// app is backgrounding but staying resident), and foreground (used when the app
-// is warm starting). Each group of steps is an ordered array of objects
-// implementing the ApplicationStep protocol.
-// Some methods (indicated below) will cause the ApplicationState to run one of
-// these lists of steps; this consists of:
-//   (1) Calling -canRunInState: on the first item in the list, passing in the
-//       running ApplicationState object. If this returns NO, stop. Otherwise:
-//   (2) Removing the first item from the list and then calling -runInState:,
-//       again passing in the current state object. State objects can assume
-//       that they are no longer in the step array once -runInState: is called.
-//   (3) When runInState: completes, going back to (1). Since the list of steps
-//       had ownership of the application step that just ran, that step will
-//       then no longer be strongly held, and will thus be deallocated unless
-//       it is being strongly held elsewhere.
-// Steps cannot themselves store state, since they don't persist after running
-// by default. Steps can write to the ApplicationState's |state| object to
-// store state.
-@interface ApplicationState : NSObject
-
-// The UIApplication instance this object is storing state for.
-@property(nonatomic, weak) UIApplication* application;
-
-// The launch options dictionary for this application, set via
-// -launchWithOptions:
-@property(nonatomic, readonly) NSDictionary* launchOptions;
-
-// The browser state this object stores; many launch steps are expected to
-// make use of this. At least one launch step must assign to this property at
-// some point in the launch sequence.
-@property(nonatomic, assign) ios::ChromeBrowserState* browserState;
-
-// The current phase the application is in. Changing this doesn't trigger
-// any launch steps; one of the phase change methods must be called to do that.
-// Steps invoked during the phase change methods must update this property.
-@property(nonatomic, assign) ApplicationPhase phase;
-
-// Persistant storage for application steps that need to have objects live
-// beyond the execution of the step. This should be used sparingly for objects
-// that actually need to persist for the lifetime of the app.
-@property(nonatomic, readonly) base::SupportsUserData* persistentState;
-
-// The window for this application. Launch steps must create this, make it key
-// and make it visible, although those three actions may be spread across
-// more than one step.
-@property(nonatomic, strong) UIWindow* window;
-
-// An object that can open URLs when the application is asked to do so by the
-// operating system.
-@property(nonatomic, weak) id<URLOpening> URLOpener;
-
-// Steps for each phase. Steps may add more steps to these arrays, and steps
-// added in this way become strongly held by this object.
-@property(nonatomic, readonly) ApplicationStepArray* launchSteps;
-@property(nonatomic, readonly) ApplicationStepArray* terminationSteps;
-@property(nonatomic, readonly) ApplicationStepArray* backgroundSteps;
-@property(nonatomic, readonly) ApplicationStepArray* foregroundSteps;
-
-// Phase change methods.
-
-// Sets the launchOptions property to |launchOptions| and then runs the launch
-// steps.
-- (void)launchWithOptions:(NSDictionary*)launchOptions;
-
-// Runs the launch steps.
-- (void)continueLaunch;
-
-// Runs the termination steps.
-- (void)terminate;
-
-// Runs the background steps.
-- (void)background;
-
-// Runs the foreground steps.
-- (void)foreground;
-
-@end
-
-#endif  // IOS_CHROME_APP_APPLICATION_STATE_H_