Reland "[ios] Hook up remote tabs in tab grid"

This reverts commit cd9fa081.

This CL fixes the reason that the DCHECK failed causing
the original revert.

Original change's description:
> Revert "[ios] Hook up remote tabs in tab grid"
>
> This reverts commit 5316b1cb.
>
> Reason for revert: breaking ios_chrome_settings_egtests
>
> Original change's description:
> > [ios] Hook up remote tabs in tab grid
> >
> > This CL hooks up the remote tabs in the tab grid.
> >
> > A user can sign in from the remote tabs page in the tab grid. The
> > transition animation that displays the signin interaction controller
> > looks bad (and we are investigating the cause). If the user is signed
> > in but does not have sync enabled, the user can enable sync from here.
> >
> > Currently, tapping on a tab does nothing. This will be enabled in a
> > future CL.
> >
> > Cq-Include-Trybots: luci.chromium.try:ios-simulator-full-configs;master.tryserver.chromium.mac:ios-simulator-cronet
> > Change-Id: Ifba06919e1fb496917254a0da7e5462a4b854d79
> > Reviewed-on: https://chromium-review.googlesource.com/1084080
> > Commit-Queue: edchin <edchin@chromium.org>
> > Reviewed-by: Eugene But <eugenebut@chromium.org>
> > Reviewed-by: Sergio Collazos <sczs@chromium.org>
> > Reviewed-by: edchin <edchin@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#564684}
>
> TBR=rohitrao@chromium.org,eugenebut@chromium.org,edchin@chromium.org,sczs@chromium.org,javierrobles@chromium.org
>
> Change-Id: Idc0b0b2def356a173949298bc7f560ee4dad3744
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Cq-Include-Trybots: luci.chromium.try:ios-simulator-full-configs;master.tryserver.chromium.mac:ios-simulator-cronet
> Reviewed-on: https://chromium-review.googlesource.com/1088566
> Reviewed-by: Olivier Robin <olivierrobin@chromium.org>
> Commit-Queue: Olivier Robin <olivierrobin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#564828}

TBR=rohitrao@chromium.org,eugenebut@chromium.org,olivierrobin@chromium.org,edchin@chromium.org,sczs@chromium.org

Change-Id: I34dca3dadbe0d356aff881559353876736722224
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Cq-Include-Trybots: luci.chromium.try:ios-simulator-full-configs;master.tryserver.chromium.mac:ios-simulator-cronet
Reviewed-on: https://chromium-review.googlesource.com/1089251Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Reviewed-by: Sergio Collazos <sczs@chromium.org>
Reviewed-by: edchin <edchin@chromium.org>
Commit-Queue: edchin <edchin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#565045}

ios/chrome/app/main_controller.mm

@@ -956,6 +956,8 @@ void MainControllerAuthenticationServiceDelegate::ClearBrowsingData(
   [_browserViewWrangler shutdown];
   _browserViewWrangler = nil;
 
+  [_mainCoordinator stop];
+
   _chromeMain.reset();
 }
 

ios/chrome/browser/ui/recent_tabs/recent_tabs_table_view_controller.mm

@@ -354,25 +354,25 @@ const int kRelativeTimeMaxHours = 4;
 // called inside a [UITableView beginUpdates] block on iOS10, or
 // performBatchUpdates on iOS11+.
 - (void)updateOtherDevicesSectionForState:(SessionsSyncUserState)newState {
-  DCHECK(newState !=
-         SessionsSyncUserState::USER_SIGNED_IN_SYNC_ON_WITH_SESSIONS);
+  DCHECK_NE(newState,
+            SessionsSyncUserState::USER_SIGNED_IN_SYNC_ON_WITH_SESSIONS);
   TableViewModel* model = self.tableViewModel;
   SessionsSyncUserState previousState = self.sessionState;
-  switch (previousState) {
-    case SessionsSyncUserState::USER_SIGNED_IN_SYNC_OFF:
-    case SessionsSyncUserState::USER_SIGNED_IN_SYNC_ON_NO_SESSIONS:
-    case SessionsSyncUserState::USER_SIGNED_OUT:
-    case SessionsSyncUserState::USER_SIGNED_IN_SYNC_IN_PROGRESS:
-      // The OtherDevices section will be updated, remove it in order to clean
-      // it up.
-      [model removeSectionWithIdentifier:SectionIdentifierOtherDevices];
-      break;
-    case SessionsSyncUserState::USER_SIGNED_IN_SYNC_ON_WITH_SESSIONS:
-      // The Sessions Section exists, remove it.
-      [self removeSessionSections];
-      break;
+  if (previousState ==
+      SessionsSyncUserState::USER_SIGNED_IN_SYNC_ON_WITH_SESSIONS) {
+    // There were previously one or more session sections, but now they will be
+    // removed and replaced with a single OtherDevices section.
+    [self removeSessionSections];
+    [self addOtherDevicesSectionForState:newState];
+    // This is a special situation where the tableview operation is an insert
+    // rather than reload because the section was deleted.
+    [self.tableView insertSections:[self otherDevicesSectionIndexSet]
+                  withRowAnimation:UITableViewRowAnimationNone];
+    return;
   }
-  // Add an updated OtherDevices Section and then reload the TableView section.
+  // For all other previous states, the tableview operation is a reload since
+  // there is already an OtherDevices section that can be updated.
+  [model removeSectionWithIdentifier:SectionIdentifierOtherDevices];
   [self addOtherDevicesSectionForState:newState];
   [self.tableView reloadSections:[self otherDevicesSectionIndexSet]
                 withRowAnimation:UITableViewRowAnimationNone];
@@ -570,6 +570,7 @@ const int kRelativeTimeMaxHours = 4;
   self.sessionState = newSessionState;
   if (self.sessionState != SessionsSyncUserState::USER_SIGNED_OUT) {
     [self.signinPromoViewMediator signinPromoViewRemoved];
+    self.signinPromoViewMediator.consumer = nil;
     self.signinPromoViewMediator = nil;
   }
 }

ios/chrome/browser/ui/tab_grid/tab_grid_coordinator.mm

@@ -68,6 +68,12 @@
                               forProtocol:@protocol(BrowserCommands)];
     [_dispatcher startDispatchingToTarget:applicationCommandEndpoint
                               forProtocol:@protocol(ApplicationCommands)];
+    // -startDispatchingToTarget:forProtocol: doesn't pick up protocols the
+    // passed protocol conforms to, so ApplicationSettingsCommands is explicitly
+    // dispatched to the endpoint as well.
+    [_dispatcher
+        startDispatchingToTarget:applicationCommandEndpoint
+                     forProtocol:@protocol(ApplicationSettingsCommands)];
   }
   return self;
 }
@@ -150,6 +156,21 @@
   mainViewController.remoteTabsViewController.browserState =
       _regularTabModel.browserState;
   self.remoteTabsMediator = [[RecentTabsMediator alloc] init];
+  self.remoteTabsMediator.browserState = _regularTabModel.browserState;
+  self.remoteTabsMediator.consumer = mainViewController.remoteTabsConsumer;
+  // TODO(crbug.com/845636) : Currently, the image data source must be set
+  // before the mediator starts updating its consumer. Fix this so that order of
+  // calls does not matter.
+  mainViewController.remoteTabsViewController.imageDataSource =
+      self.remoteTabsMediator;
+  mainViewController.remoteTabsViewController.delegate =
+      self.remoteTabsMediator;
+  mainViewController.remoteTabsViewController.dispatcher =
+      static_cast<id<ApplicationCommands>>(self.dispatcher);
+  if (self.remoteTabsMediator.browserState) {
+    [self.remoteTabsMediator initObservers];
+    [self.remoteTabsMediator refreshSessionsView];
+  }
 
   // Once the mediators are set up, stop keeping pointers to the tab models used
   // to initialize them.
@@ -162,6 +183,8 @@
 - (void)stop {
   [self.dispatcher stopDispatchingForProtocol:@protocol(BrowserCommands)];
   [self.dispatcher stopDispatchingForProtocol:@protocol(ApplicationCommands)];
+  [self.dispatcher
+      stopDispatchingForProtocol:@protocol(ApplicationSettingsCommands)];
 
   // TODO(crbug.com/845192) : RecentTabsTableViewController behaves like a
   // coordinator and that should be factored out.