[ios] Properly dismiss history in tab grid

History coordinator can now be started on top of the tab grid.
This history coordinator was not properly being dismissed
inside main_controller's |-dismissModalDialogsWithCompletion:|.

As part of fixing dismissal, this CL also fixes a bookkeeping flaw
in main_controller. Previously, main_controller conflated the
existence of |self.currentBVC| with the BVC being presented and active.
This CL changes that logic to use |-isTabSwitcherActive| instead.

Bug : 852243

Cq-Include-Trybots: luci.chromium.try:ios-simulator-full-configs;master.tryserver.chromium.mac:ios-simulator-cronet
Change-Id: I93d5efb33a2de8eaed7b0472fa2994c14603d11a
Reviewed-on: https://chromium-review.googlesource.com/1098555
Commit-Queue: edchin <edchin@chromium.org>
Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Reviewed-by: Mark Cogan <marq@chromium.org>
Reviewed-by: edchin <edchin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#567172}

ios/chrome/app/application_delegate/url_opener_unittest.mm

@@ -108,6 +108,12 @@ typedef Tab* (^mock_gurl_nsuinteger_pagetransition)(const GURL&,
   return nil;
 }
 
+- (void)clearPresentedStateWithCompletion:(ProceduralBlock)completion
+                           dismissOmnibox:(BOOL)dismissOmnibox {
+  if (completion)
+    completion();
+}
+
 - (void)expectNewForegroundTab {
   // no-op.
 }
@@ -242,6 +248,8 @@ TEST_F(URLOpenerTest, HandleOpenURLWithOpenTabs) {
       static_cast<BrowserViewController*>(bvc_mock);
   controller.browserViewInformation.otrBVC =
       static_cast<BrowserViewController*>(otr_bvc_mock);
+  controller.browserViewInformation.currentBVC =
+      static_cast<BrowserViewController*>(bvc_mock);
 
   NSDictionary<NSString*, id>* options = nil;
   [URLOpener openURL:url

ios/chrome/app/main_controller.mm

@@ -2345,21 +2345,34 @@ void MainControllerAuthenticationServiceDelegate::ClearBrowsingData(
   // Then, depending on what the SSO view controller is presented on, dismiss
   // it.
   ProceduralBlock completionWithBVC = ^{
+    DCHECK(self.currentBVC);
+    DCHECK(![self isTabSwitcherActive]);
     // This will dismiss the SSO view controller.
     [self.currentBVC clearPresentedStateWithCompletion:completion
                                         dismissOmnibox:dismissOmnibox];
   };
   ProceduralBlock completionWithoutBVC = ^{
+    // |self.currentBVC| may exist but tab switcher should be active.
+    DCHECK([self isTabSwitcherActive]);
     // This will dismiss the SSO view controller.
     [self dismissSigninInteractionCoordinator];
-    if (completion)
+    if (GetTabSwitcherMode() == TabSwitcherMode::GRID) {
+      // History coordinator can be started on top of the tab grid. This is not
+      // true of the other tab switchers.
+      DCHECK(self.mainCoordinator);
+      TabGridCoordinator* tabGridCoordinator =
+          base::mac::ObjCCastStrict<TabGridCoordinator>(self.mainCoordinator);
+      [tabGridCoordinator stopChildCoordinatorsWithCompletion:completion];
+    } else if (completion) {
+      // Run completion separately if not in tab grid.
       completion();
+    }
   };
 
   // As a top level rule, if the settings are showing, they need to be
   // dismissed. Then, based on whether the BVC is present or not, a different
   // completion callback is called.
-  if (self.currentBVC && _settingsNavigationController) {
+  if (![self isTabSwitcherActive] && _settingsNavigationController) {
     // In this case, the settings are up and the BVC is showing. Close the
     // settings then call the BVC completion.
     [self closeSettingsAnimated:NO completion:completionWithBVC];
@@ -2367,7 +2380,7 @@ void MainControllerAuthenticationServiceDelegate::ClearBrowsingData(
     // In this case, the settings are up but the BVC is not showing. Close the
     // settings then call the no-BVC completion.
     [self closeSettingsAnimated:NO completion:completionWithoutBVC];
-  } else if (self.currentBVC) {
+  } else if (![self isTabSwitcherActive]) {
     // In this case, the settings are not shown but the BVC is showing. Call the
     // BVC completion.
     completionWithBVC();

ios/chrome/browser/ui/history/history_coordinator.h

@@ -7,6 +7,7 @@
 
 #import <UIKit/UIKit.h>
 
+#import "base/ios/block_types.h"
 #import "ios/chrome/browser/ui/coordinators/chrome_coordinator.h"
 
 @protocol ApplicationCommands;
@@ -22,6 +23,8 @@
 @property(nonatomic, weak) id<UrlLoader> loader;
 // Delegate used to make the Tab UI visible.
 @property(nonatomic, weak) id<HistoryPresentationDelegate> presentationDelegate;
+// Stops this Coordinator then calls |completionHandler|.
+- (void)stopWithCompletion:(ProceduralBlock)completionHandler;
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_HISTORY_HISTORY_COORDINATOR_H_

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

@@ -7,6 +7,7 @@
 
 #import <Foundation/Foundation.h>
 
+#import "base/ios/block_types.h"
 #import "ios/chrome/browser/ui/main/main_coordinator.h"
 #import "ios/chrome/browser/ui/main/view_controller_swapping.h"
 
@@ -33,6 +34,10 @@
 // without animation.  This should only be used by unittests.
 @property(nonatomic, readwrite, assign) BOOL animationsDisabledForTesting;
 
+// Stops all child coordinators then calls |completion|. |completion| is called
+// whether or not child coordinators exist.
+- (void)stopChildCoordinatorsWithCompletion:(ProceduralBlock)completion;
+
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_TAB_GRID_TAB_GRID_COORDINATOR_H_

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

@@ -91,7 +91,7 @@
   return self;
 }
 
-#pragma mark - Public properties
+#pragma mark - Public
 
 - (id<TabSwitcher>)tabSwitcher {
   return self.adaptor;
@@ -127,6 +127,15 @@
   }
 }
 
+- (void)stopChildCoordinatorsWithCompletion:(ProceduralBlock)completion {
+  // History may be presented on top of the tab grid.
+  if (self.historyCoordinator) {
+    [self.historyCoordinator stopWithCompletion:completion];
+  } else if (completion) {
+    completion();
+  }
+}
+
 #pragma mark - MainCoordinator properties
 
 - (id<ViewControllerSwapping>)viewControllerSwapper {