[iOS] UnifiedConsentCoordinator.selectedIdentity changed to readwrite

|selectedIdentity| has to be set when starting UnifiedConsentCoordinator.
This API is required to support sign-in promo with the "Continue as"
button.
Also the avatar has to be updated when an update notification is
received by ChromeIdentityServiceObserver.

Related to:
crrev.com/c/1009906
crrev.com/c/1010346

Bug: 827072
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: I800294f36178a2776e03d28c625f234e4ecc1d2b
Reviewed-on: https://chromium-review.googlesource.com/1025895
Commit-Queue: Jérôme Lebel <jlebel@chromium.org>
Reviewed-by: Gauthier Ambard <gambard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#553959}

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

@@ -17,7 +17,7 @@
 
 // Called when the user taps on the settings link.
 - (void)unifiedConsentCoordinatorDidTapSettingsLink:
-    (UnifiedConsentCoordinator*)controller;
+    (UnifiedConsentCoordinator*)coordinator;
 
 @end
 
@@ -29,8 +29,11 @@
 @interface UnifiedConsentCoordinator : NSObject
 
 @property(nonatomic, weak) id<UnifiedConsentCoordinatorDelegate> delegate;
-// Identity selected by the user to sign-in.
-@property(nonatomic, strong, readonly) ChromeIdentity* selectedIdentity;
+// Identity selected by the user to sign-in. By default, the first identity from
+// GetAllIdentitiesSortedForDisplay() is used. If there is no identity in the
+// list, the identity picker will be hidden. Nil is not accepted if at least one
+// identity exists.
+@property(nonatomic, strong) ChromeIdentity* selectedIdentity;
 // String id for text to open the settings (related to record the user consent).
 @property(nonatomic, readonly) int openSettingsStringId;
 // View controller used to display the view.

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

@@ -26,12 +26,17 @@
 @synthesize unifiedConsentMediator = _unifiedConsentMediator;
 @synthesize unifiedConsentViewController = _unifiedConsentViewController;
 
+- (instancetype)init {
+  if (self) {
+    _unifiedConsentViewController = [[UnifiedConsentViewController alloc] init];
+    _unifiedConsentViewController.delegate = self;
+    _unifiedConsentMediator = [[UnifiedConsentMediator alloc]
+        initWithUnifiedConsentViewController:_unifiedConsentViewController];
+  }
+  return self;
+}
+
 - (void)start {
-  self.unifiedConsentViewController =
-      [[UnifiedConsentViewController alloc] init];
-  self.unifiedConsentViewController.delegate = self;
-  self.unifiedConsentMediator = [[UnifiedConsentMediator alloc]
-      initWithUnifiedConsentViewController:self.unifiedConsentViewController];
   [self.unifiedConsentMediator start];
 }
 
@@ -39,6 +44,10 @@
   return self.unifiedConsentMediator.selectedIdentity;
 }
 
+- (void)setSelectedIdentity:(ChromeIdentity*)selectedIdentity {
+  self.unifiedConsentMediator.selectedIdentity = selectedIdentity;
+}
+
 - (UIViewController*)viewController {
   return self.unifiedConsentViewController;
 }

ios/chrome/browser/ui/authentication/unified_consent_mediator.h

@@ -14,8 +14,11 @@
 // updates the UnifiedConsentViewController.
 @interface UnifiedConsentMediator : NSObject
 
-// Identity selected by the user to sign-in.
-@property(nonatomic) ChromeIdentity* selectedIdentity;
+// Identity selected by the user to sign-in. By default, the first identity from
+// GetAllIdentitiesSortedForDisplay() is used. If there is no identity in the
+// list, the identity picker will be hidden. Nil is not accepted if at least one
+// identity exists.
+@property(nonatomic, strong) ChromeIdentity* selectedIdentity;
 
 - (instancetype)initWithUnifiedConsentViewController:
     (UnifiedConsentViewController*)viewController NS_DESIGNATED_INITIALIZER;

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

@@ -37,40 +37,38 @@
   self = [super init];
   if (self) {
     _unifiedConsentViewController = viewController;
+    _identityServiceObserver =
+        std::make_unique<ChromeIdentityServiceObserverBridge>(self);
+    _browserProviderObserver =
+        std::make_unique<ChromeBrowserProviderObserverBridge>(self);
+    NSArray* identities = ios::GetChromeBrowserProvider()
+                              ->GetChromeIdentityService()
+                              ->GetAllIdentitiesSortedForDisplay();
+    if (identities.count != 0) {
+      _selectedIdentity = identities[0];
+    }
   }
   return self;
 }
 
 - (void)setSelectedIdentity:(ChromeIdentity*)selectedIdentity {
-  if (selectedIdentity == self.selectedIdentity)
+  if (selectedIdentity == self.selectedIdentity) {
     return;
+  }
+  // nil is allowed only if there is no other identity.
+  DCHECK(selectedIdentity || ios::GetChromeBrowserProvider()
+                                     ->GetChromeIdentityService()
+                                     ->GetAllIdentitiesSortedForDisplay()
+                                     .count == 0);
   _selectedIdentity = selectedIdentity;
   self.selectedIdentityAvatar = nil;
-  __weak UnifiedConsentMediator* weakSelf = self;
-  ios::GetChromeBrowserProvider()
-      ->GetChromeIdentityService()
-      ->GetAvatarForIdentity(self.selectedIdentity, ^(UIImage* identityAvatar) {
-        if (weakSelf.selectedIdentity != selectedIdentity) {
-          return;
-        }
-        [weakSelf identityAvatarUpdated:identityAvatar];
-      });
   [self updateViewController];
 }
 
 - (void)start {
-  _identityServiceObserver =
-      std::make_unique<ChromeIdentityServiceObserverBridge>(self);
-  _browserProviderObserver =
-      std::make_unique<ChromeBrowserProviderObserverBridge>(self);
-  NSArray* identities = ios::GetChromeBrowserProvider()
-                            ->GetChromeIdentityService()
-                            ->GetAllIdentitiesSortedForDisplay();
   // Make sure the view is loaded so the mediator can set it up.
   [self.unifiedConsentViewController loadViewIfNeeded];
-  if (identities.count != 0) {
-    self.selectedIdentity = identities[0];
-  }
+  [self updateViewController];
 }
 
 #pragma mark - Private
@@ -84,6 +82,15 @@
                                                      .userEmail];
     [self.unifiedConsentViewController
         updateIdentityPickerViewWithAvatar:self.selectedIdentityAvatar];
+    ChromeIdentity* selectedIdentity = self.selectedIdentity;
+    __weak UnifiedConsentMediator* weakSelf = self;
+    ios::GetChromeBrowserProvider()
+        ->GetChromeIdentityService()
+        ->GetAvatarForIdentity(selectedIdentity, ^(UIImage* identityAvatar) {
+          if (weakSelf.selectedIdentity != selectedIdentity)
+            return;
+          [weakSelf identityAvatarUpdated:identityAvatar];
+        });
   } else {
     [self.unifiedConsentViewController hideIdentityPickerView];
   }
@@ -112,14 +119,14 @@
 #pragma mark - ChromeIdentityServiceObserver
 
 - (void)identityListChanged {
-  ChromeIdentity* newIdentity = nil;
   NSArray* identities = ios::GetChromeBrowserProvider()
                             ->GetChromeIdentityService()
                             ->GetAllIdentitiesSortedForDisplay();
-  if (identities.count != 0) {
-    newIdentity = identities[0];
-  }
-  if (newIdentity != self.selectedIdentity) {
+  if (![identities containsObject:self.selectedIdentity]) {
+    ChromeIdentity* newIdentity = nil;
+    if (identities.count != 0) {
+      newIdentity = identities[0];
+    }
     self.selectedIdentity = newIdentity;
   }
 }