[iOS][coordinator] Modernize Unified Consent Coordinator.

This CL modernizes the UnifiedConsentCoordinator to use |browser| in
the initializer. This CL includes migration to ChromeCoordinator as a
superclass.

Bug: 1029346, 1048685
Change-Id: Ie2ce333091fcfcc9ed37fef74b2d71b254105f52
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2068597Reviewed-by: Mark Cogan <marq@chromium.org>
Commit-Queue: Nazerke Kalidolda <nazerke@google.com>
Cr-Commit-Position: refs/heads/master@{#743898}

ios/chrome/browser/ui/authentication/chrome_signin_view_controller.mm

@@ -692,7 +692,9 @@ enum AuthenticationState {
     // The user can refuse to sign-in into a managed account, so the state
     // returns to "IdentityPicker". In that case, there is no need to create a
     // new UnifiedConsentCoordinator. The current one should be used.
-    _unifiedConsentCoordinator = [[UnifiedConsentCoordinator alloc] init];
+    _unifiedConsentCoordinator = [[UnifiedConsentCoordinator alloc]
+        initWithBaseViewController:nil
+                           browser:self.browser];
     _unifiedConsentCoordinator.delegate = self;
     if (_selectedIdentity)
       _unifiedConsentCoordinator.selectedIdentity = _selectedIdentity;

ios/chrome/browser/ui/authentication/signin/user_signin/user_signin_coordinator.mm

@@ -59,7 +59,9 @@ using signin_metrics::PromoAction;
   self.viewController = [[UserSigninViewController alloc] init];
   self.viewController.delegate = self;
 
-  self.unifiedConsentCoordinator = [[UnifiedConsentCoordinator alloc] init];
+  self.unifiedConsentCoordinator = [[UnifiedConsentCoordinator alloc]
+      initWithBaseViewController:nil
+                         browser:self.browser];
   self.unifiedConsentCoordinator.delegate = self;
 
   // Set UnifiedConsentCoordinator properties.

ios/chrome/browser/ui/authentication/unified_consent/BUILD.gn

@@ -16,8 +16,10 @@ source_set("unified_consent") {
     ":unified_consent_ui",
     "//base",
     "//ios/chrome/browser",
+    "//ios/chrome/browser/main:public",
     "//ios/chrome/browser/signin",
     "//ios/chrome/browser/ui/authentication/unified_consent/identity_chooser",
+    "//ios/chrome/browser/ui/coordinators:chrome_coordinators",
     "//ios/public/provider/chrome/browser/signin",
   ]
 }

ios/chrome/browser/ui/authentication/unified_consent/unified_consent_coordinator.h

@@ -5,7 +5,7 @@
 #ifndef IOS_CHROME_BROWSER_UI_AUTHENTICATION_UNIFIED_CONSENT_UNIFIED_CONSENT_COORDINATOR_H_
 #define IOS_CHROME_BROWSER_UI_AUTHENTICATION_UNIFIED_CONSENT_UNIFIED_CONSENT_COORDINATOR_H_
 
-#import <UIKit/UIKit.h>
+#import "ios/chrome/browser/ui/coordinators/chrome_coordinator.h"
 
 #include <vector>
 
@@ -42,7 +42,15 @@
 // All the string ids displayed by the view are available with
 // |consentStringIds| and |openSettingsStringId|. Those can be used to record
 // the consent agreed by the user.
-@interface UnifiedConsentCoordinator : NSObject
+@interface UnifiedConsentCoordinator : ChromeCoordinator
+
+// Unavailable, use -initWithBaseViewController:browser:.
+- (instancetype)initWithBaseViewController:(UIViewController*)viewController
+    NS_UNAVAILABLE;
+// Unavailable, use -initWithBaseViewController:browser:.
+- (instancetype)initWithBaseViewController:(UIViewController*)viewController
+                              browserState:(ChromeBrowserState*)browserState
+    NS_UNAVAILABLE;
 
 @property(nonatomic, weak) id<UnifiedConsentCoordinatorDelegate> delegate;
 // Identity selected by the user to sign-in. By default, the first identity from
@@ -66,9 +74,6 @@
 // ChromeSigninViewController.
 @property(nonatomic, assign, getter=isUIDisabled) BOOL uiDisabled;
 
-// Starts this coordinator.
-- (void)start;
-
 // List of string ids used for the user consent. The string ids order matches
 // the way they appear on the screen.
 - (const std::vector<int>&)consentStringIds;

ios/chrome/browser/ui/authentication/unified_consent/unified_consent_coordinator.mm

@@ -5,6 +5,7 @@
 #include "ios/chrome/browser/ui/authentication/unified_consent/unified_consent_coordinator.h"
 
 #include "base/logging.h"
+#import "ios/chrome/browser/main/browser.h"
 #import "ios/chrome/browser/ui/authentication/unified_consent/identity_chooser/identity_chooser_coordinator.h"
 #import "ios/chrome/browser/ui/authentication/unified_consent/identity_chooser/identity_chooser_coordinator_delegate.h"
 #import "ios/chrome/browser/ui/authentication/unified_consent/unified_consent_mediator.h"
@@ -34,8 +35,9 @@
 
 @implementation UnifiedConsentCoordinator
 
-- (instancetype)init {
-  self = [super init];
+- (instancetype)initWithBaseViewController:(UIViewController*)viewController
+                                   browser:(Browser*)browser {
+  self = [super initWithBaseViewController:nil browser:browser];
   if (self) {
     _unifiedConsentViewController = [[UnifiedConsentViewController alloc] init];
     _unifiedConsentViewController.delegate = self;