Revert "Do not recover incognito tabs if user deliberately terminates Chrome."

This reverts commit 0928665a.

Reason for revert: This behavior is causing more confusion for users than it is helping. See crbug.com/854274 for details.

Original change's description:
> Do not recover incognito tabs if user deliberately terminates Chrome.
>
> Previously incognito tabs were always recovered no matter how the app
> was last shutdown.
>
> Instead, do not restore the incognito tabs if the user explicitly closes
> Chrome. If the system terminates the app, the tabs should be restored.
> (This can happen at any time and without user notice, so such
> terminations should not lead to a loss of the user's incognito tabs.)
>
> Bug: 653248
> Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
> Change-Id: I018cdf5cda2004e32e1010c4d9bab4bd10c0ae99
> Reviewed-on: https://chromium-review.googlesource.com/835532
> Reviewed-by: Eugene But <eugenebut@chromium.org>
> Commit-Queue: Mike Dougherty <michaeldo@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#526099}

TBR=marq@chromium.org,eugenebut@chromium.org,michaeldo@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 653248, 854274
Change-Id: I952db05d6364d0944c3e46b9fa78b1432e889830
Cq-Include-Trybots: luci.chromium.try:ios-simulator-full-configs;master.tryserver.chromium.mac:ios-simulator-cronet
Reviewed-on: https://chromium-review.googlesource.com/1106777
Commit-Queue: Mike Dougherty <michaeldo@chromium.org>
Reviewed-by: Mike Dougherty <michaeldo@chromium.org>
Reviewed-by: Eugene But <eugenebut@chromium.org>
Cr-Commit-Position: refs/heads/master@{#568603}

ios/chrome/app/application_delegate/app_state.mm

@@ -395,15 +395,7 @@ initWithBrowserLauncher:(id<BrowserLauncher>)browserLauncher
   // closing the tabs. Set the BVC to inactive to cancel all the dialogs.
   if ([_browserLauncher browserInitializationStage] >=
       INITIALIZATION_STAGE_FOREGROUND) {
-    [[_browserLauncher browserViewInformation].mainTabModel haltAllTabs];
-
-    // Application termination flow is only triggered on a shutdown deliberately
-    // triggered by a user. In this case, close all incognito tabs.
-    TabModel* OTRTabModel =
-        [_browserLauncher browserViewInformation].otrTabModel;
-    [OTRTabModel closeAllTabs];
-    [OTRTabModel saveSessionImmediately:YES];
-
+    [[_browserLauncher browserViewInformation] haltAllTabs];
     [_browserLauncher browserViewInformation].currentBVC.active = NO;
   }
 

ios/chrome/app/application_delegate/app_state_unittest.mm

@@ -524,14 +524,10 @@ TEST_F(AppStateWithThreadTest, willTerminate) {
   id window = [OCMockObject mockForClass:[UIWindow class]];
   id browserViewInformation =
       [OCMockObject mockForProtocol:@protocol(BrowserViewInformation)];
-  id mainTabModel = [OCMockObject mockForClass:[TabModel class]];
-  id OTRTabModel = [OCMockObject mockForClass:[TabModel class]];
   [[[browserLauncher stub] andReturnValue:@(INITIALIZATION_STAGE_FOREGROUND)]
       browserInitializationStage];
   [[[browserLauncher stub] andReturn:browserViewInformation]
       browserViewInformation];
-  [[[browserViewInformation stub] andReturn:mainTabModel] mainTabModel];
-  [[[browserViewInformation stub] andReturn:OTRTabModel] otrTabModel];
   [[[browserViewInformation stub] andReturn:browserViewController] currentBVC];
 
   id settingsNavigationController =
@@ -543,11 +539,7 @@ TEST_F(AppStateWithThreadTest, willTerminate) {
   [[appNavigation expect] closeSettingsAnimated:NO completion:nil];
 
   [[browserViewInformation expect] cleanDeviceSharingManager];
-
-  [[mainTabModel expect] haltAllTabs];
-
-  [[OTRTabModel expect] closeAllTabs];
-  [[OTRTabModel expect] saveSessionImmediately:YES];
+  [[browserViewInformation expect] haltAllTabs];
 
   id startupInformation =
       [OCMockObject mockForProtocol:@protocol(StartupInformation)];
@@ -566,8 +558,6 @@ TEST_F(AppStateWithThreadTest, willTerminate) {
                applicationNavigation:appNavigation];
 
   // Test.
-  EXPECT_OCMOCK_VERIFY(OTRTabModel);
-  EXPECT_OCMOCK_VERIFY(mainTabModel);
   EXPECT_OCMOCK_VERIFY(browserViewController);
   EXPECT_OCMOCK_VERIFY(startupInformation);
   EXPECT_OCMOCK_VERIFY(appNavigation);

ios/chrome/app/main_controller.mm

@@ -967,6 +967,10 @@ void MainControllerAuthenticationServiceDelegate::ClearBrowsingData(
 
 #pragma mark - BrowserViewInformation implementation.
 
+- (void)haltAllTabs {
+  [_browserViewWrangler haltAllTabs];
+}
+
 - (void)cleanDeviceSharingManager {
   [_browserViewWrangler cleanDeviceSharingManager];
 }

ios/chrome/browser/ui/main/browser_view_information.h

@@ -29,6 +29,9 @@ class ChromeBrowserState;
 // otrBVC). The other, if present, is in suspended mode.
 @property(nonatomic, assign) BrowserViewController* currentBVC;
 
+// Halts all tabs from all TabModels.
+- (void)haltAllTabs;
+
 // Returns the browser state corresponding to the current browser view.
 - (ios::ChromeBrowserState*)currentBrowserState;
 

ios/chrome/browser/ui/main/browser_view_wrangler.mm

@@ -221,6 +221,11 @@
   return self.currentBVC.browserState;
 }
 
+- (void)haltAllTabs {
+  [self.mainTabModel haltAllTabs];
+  [self.otrTabModel haltAllTabs];
+}
+
 - (void)cleanDeviceSharingManager {
   [self.deviceSharingManager updateBrowserState:NULL];
 }