Revert "[ios] Ensure proper shutdown of Chrome on iOS."

This reverts commit 1c7e3e09.

Breaks PhoneSimulator and TabletSimulator bots:

Failed steps failed ios_chrome_integration_egtests (iphone 5 ios 10.0) on mac failed ios_chrome_settings_egtests (iphone 5 ios 10.0) on mac failed ios_chrome_ui_egtests (iphone 5 ios 10.0) on mac failed ios_chrome_external_url_egtests (iphone 5 ios 10.0) on mac failed ios_internal_chrome_external_url_egtests (iphone 5 ios 10.0) on mac failed failure reason

[0612/124347.435892:FATAL:browser_view_controller.mm(995)] Check failed: _isShutdown. -shutdown must be called before dealloc.

TBR=sdefresne@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2930363003
Cr-Commit-Position: refs/heads/master@{#478783}

ios/chrome/app/application_delegate/url_opener_unittest.mm

@@ -77,7 +77,6 @@ typedef Tab* (^mock_gurl_nsuinteger_pagetransition)(const GURL&,
 - (void)expectNewForegroundTab;
 - (void)setActive:(BOOL)active;
 - (TabModel*)tabModel;
-- (void)shutdown;
 @end
 
 @implementation URLOpenerMockBVC
@@ -111,19 +110,10 @@ typedef Tab* (^mock_gurl_nsuinteger_pagetransition)(const GURL&,
   return nil;
 }
 
-- (void)shutdown {
-  // no-op
-}
-
 @end
 
 class URLOpenerTest : public PlatformTest {
  protected:
-  void TearDown() override {
-    [main_controller_ stopChromeMain];
-    PlatformTest::TearDown();
-  }
-
   MainController* GetMainController() {
     if (!main_controller_) {
       main_controller_ = [[MainController alloc] init];

ios/chrome/app/main_controller.mm

@@ -680,7 +680,6 @@ enum class StackViewDismissalMode { NONE, NORMAL, INCOGNITO };
   // Initialize and set the main browser state.
   [self initializeBrowserState:chromeBrowserState];
   _mainBrowserState = chromeBrowserState;
-  [_browserViewWrangler shutdown];
   _browserViewWrangler =
       [[BrowserViewWrangler alloc] initWithBrowserState:_mainBrowserState
                                        tabModelObserver:self];
@@ -911,7 +910,6 @@ enum class StackViewDismissalMode { NONE, NORMAL, INCOGNITO };
   [_spotlightManager shutdown];
   _spotlightManager = nil;
 
-  [_browserViewWrangler shutdown];
   _browserViewWrangler = nil;
 
   _chromeMain.reset();
@@ -2553,7 +2551,6 @@ enum class StackViewDismissalMode { NONE, NORMAL, INCOGNITO };
   // Create a BrowserViewWrangler with a null browser state. This will trigger
   // assertions if the BrowserViewWrangler is asked to create any BVC or
   // tabModel objects, but it will accept assignments to them.
-  [_browserViewWrangler shutdown];
   _browserViewWrangler =
       [[BrowserViewWrangler alloc] initWithBrowserState:nullptr
                                        tabModelObserver:self];

ios/chrome/app/main_controller_unittest.mm

@@ -56,11 +56,6 @@ typedef void (^HandleLaunchOptions)(id self,
 
 class TabOpenerTest : public PlatformTest {
  protected:
-  void TearDown() override {
-    [main_controller_ stopChromeMain];
-    PlatformTest::TearDown();
-  }
-
   BOOL swizzleHasBeenCalled() { return swizzle_block_executed_; }
 
   void swizzleHandleLaunchOptions(

ios/chrome/browser/ui/browser_view_controller.h

@@ -155,9 +155,6 @@ extern NSString* const kLocationBarResignsFirstResponderNotification;
 - (void)removeExternalFilesImmediately:(BOOL)immediately
                      completionHandler:(ProceduralBlock)completionHandler;
 
-// Called before the instance is deallocated.
-- (void)shutdown;
-
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_BROWSER_VIEW_CONTROLLER_H_

ios/chrome/browser/ui/browser_view_controller.mm

@@ -471,9 +471,6 @@ NSString* const kNativeControllerTemporaryKey = @"NativeControllerTemporaryKey";
   // YES if waiting for a foreground tab due to expectNewForegroundTab.
   BOOL _expectingForegroundTab;
 
-  // Whether or not -shutdown has been called.
-  BOOL _isShutdown;
-
   // The ChromeBrowserState associated with this BVC.
   ios::ChromeBrowserState* _browserState;  // weak
 
@@ -992,7 +989,19 @@ class BrowserBookmarkModelBridge : public bookmarks::BookmarkModelObserver {
 }
 
 - (void)dealloc {
-  DCHECK(_isShutdown) << "-shutdown must be called before dealloc.";
+  _tabStripController = nil;
+  _infoBarContainer = nil;
+  _readingListMenuNotifier = nil;
+  if (_bookmarkModel)
+    _bookmarkModel->RemoveObserver(_bookmarkModelBridge.get());
+  [_model removeObserver:self];
+  [[UpgradeCenter sharedInstance] unregisterClient:self];
+  [[NSNotificationCenter defaultCenter] removeObserver:self];
+  [_toolbarController setDelegate:nil];
+  if (_voiceSearchController)
+    _voiceSearchController->SetDelegate(nil);
+  [_rateThisAppDialog setDelegate:nil];
+  [_model closeAllTabs];
 }
 
 #pragma mark - Accessibility
@@ -2258,25 +2267,6 @@ class BrowserBookmarkModelBridge : public bookmarks::BookmarkModelObserver {
                                              }));
 }
 
-- (void)shutdown {
-  DCHECK(!_isShutdown);
-  _isShutdown = YES;
-
-  _tabStripController = nil;
-  _infoBarContainer = nil;
-  _readingListMenuNotifier = nil;
-  if (_bookmarkModel)
-    _bookmarkModel->RemoveObserver(_bookmarkModelBridge.get());
-  [_model removeObserver:self];
-  [[UpgradeCenter sharedInstance] unregisterClient:self];
-  [[NSNotificationCenter defaultCenter] removeObserver:self];
-  [_toolbarController setDelegate:nil];
-  if (_voiceSearchController)
-    _voiceSearchController->SetDelegate(nil);
-  [_rateThisAppDialog setDelegate:nil];
-  [_model closeAllTabs];
-}
-
 #pragma mark - SnapshotOverlayProvider methods
 
 - (NSArray*)snapshotOverlaysForTab:(Tab*)tab {

ios/chrome/browser/ui/browser_view_controller_unittest.mm

@@ -263,8 +263,6 @@ class BrowserViewControllerTest : public BlockCleanupTest {
 
   void TearDown() override {
     [[bvc_ view] removeFromSuperview];
-    [bvc_ shutdown];
-
     BlockCleanupTest::TearDown();
   }
 

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

@@ -57,9 +57,6 @@ class ChromeBrowserState;
 - (void)deleteIncognitoTabModelState:
     (BrowsingDataRemovalController*)removalController;
 
-// Called before the instance is deallocated.
-- (void)shutdown;
-
 @end
 
 @interface BrowserViewWrangler (Testing)

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

@@ -27,7 +27,6 @@
 @interface BrowserViewWrangler ()<TabModelObserver> {
   ios::ChromeBrowserState* _browserState;
   __unsafe_unretained id<TabModelObserver> _tabModelObserver;
-  BOOL _isShutdown;
 
   base::mac::ObjCPropertyReleaser _propertyReleaser_BrowserViewWrangler;
 }
@@ -83,7 +82,25 @@
 }
 
 - (void)dealloc {
-  DCHECK(_isShutdown) << "-shutdown must be called before -dealloc";
+  if (_tabModelObserver) {
+    [_mainTabModel removeObserver:_tabModelObserver];
+    [_otrTabModel removeObserver:_tabModelObserver];
+  }
+  [_mainTabModel removeObserver:self];
+  [_otrTabModel removeObserver:self];
+
+  // Stop URL monitoring of the main tab model.
+  ios_internal::breakpad::StopMonitoringURLsForTabModel(_mainTabModel);
+
+  // Stop Breakpad state monitoring of both tab models (if necessary).
+  ios_internal::breakpad::StopMonitoringTabStateForTabModel(_mainTabModel);
+  ios_internal::breakpad::StopMonitoringTabStateForTabModel(_otrTabModel);
+
+  // Normally other objects will take care of unhooking the tab models from
+  // the browser state, but this code should ensure that it happens regardless.
+  [_mainTabModel browserStateDestroyed];
+  [_otrTabModel browserStateDestroyed];
+
   [super dealloc];
 }
 
@@ -266,39 +283,6 @@
   }
 }
 
-- (void)shutdown {
-  DCHECK(!_isShutdown);
-  _isShutdown = YES;
-
-  if (_tabModelObserver) {
-    [_mainTabModel removeObserver:_tabModelObserver];
-    [_otrTabModel removeObserver:_tabModelObserver];
-    _tabModelObserver = nil;
-  }
-
-  [_mainTabModel removeObserver:self];
-  [_otrTabModel removeObserver:self];
-
-  // Stop URL monitoring of the main tab model.
-  ios_internal::breakpad::StopMonitoringURLsForTabModel(_mainTabModel);
-
-  // Stop Breakpad state monitoring of both tab models (if necessary).
-  ios_internal::breakpad::StopMonitoringTabStateForTabModel(_mainTabModel);
-  ios_internal::breakpad::StopMonitoringTabStateForTabModel(_otrTabModel);
-
-  // Normally other objects will take care of unhooking the tab models from
-  // the browser state, but this code should ensure that it happens regardless.
-  [_mainTabModel browserStateDestroyed];
-  [_otrTabModel browserStateDestroyed];
-
-  [_mainBVC shutdown];
-  [_otrBVC shutdown];
-  self.mainBVC = nil;
-  self.otrBVC = nil;
-
-  _browserState = nullptr;
-}
-
 #pragma mark - Internal methods
 
 - (TabModel*)buildOtrTabModel:(BOOL)empty {

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

@@ -50,8 +50,6 @@ TEST_F(BrowserViewWranglerTest, TestInitNilObserver) {
   EXPECT_NE(bvc, [wrangler otrBVC]);
   EXPECT_NE(tabModel, [wrangler otrTabModel]);
   EXPECT_TRUE([wrangler otrTabModel].browserState->IsOffTheRecord());
-
-  [wrangler shutdown];
 }
 
 }  // namespace