[iOS] Create OverlayPresentationContextFullscreenDisabler.

Rather than being owned by the OverlayContainerCoordinator, this CL
moves this functionality to a separate object owned by the
OverlayPresentationContext.  This will allow it to be used in a
follow-up CL when the overlay container functionality is split
between multiple coordinators.

Bug: 1030357
Change-Id: I38a6e7d179e119b180059df1e1a78b10029548b3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2056110
Commit-Queue: Kurt Horimoto <kkhorimoto@chromium.org>
Reviewed-by: Sergio Collazos <sczs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#741527}

ios/chrome/browser/ui/overlays/BUILD.gn

@@ -11,6 +11,8 @@ source_set("overlays") {
     "overlay_container_coordinator.mm",
     "overlay_coordinator_factory+initialization.h",
     "overlay_coordinator_factory.mm",
+    "overlay_presentation_context_fullscreen_disabler.h",
+    "overlay_presentation_context_fullscreen_disabler.mm",
     "overlay_presentation_context_impl.h",
     "overlay_presentation_context_impl.mm",
     "overlay_request_ui_state.h",
@@ -89,6 +91,7 @@ source_set("unit_tests") {
   testonly = true
   sources = [
     "overlay_container_coordinator_unittest.mm",
+    "overlay_presentation_context_fullscreen_disabler_unittest.mm",
     "overlay_request_mediator_unittest.mm",
     "overlay_request_mediator_util_unittest.mm",
     "overlay_request_ui_state_unittest.mm",

ios/chrome/browser/ui/overlays/overlay_container_coordinator.mm

@@ -10,10 +10,6 @@
 #include "base/logging.h"
 #include "base/scoped_observer.h"
 #import "ios/chrome/browser/main/browser.h"
-#import "ios/chrome/browser/overlays/public/overlay_presenter.h"
-#import "ios/chrome/browser/overlays/public/overlay_presenter_observer.h"
-#import "ios/chrome/browser/ui/fullscreen/animated_scoped_fullscreen_disabler.h"
-#import "ios/chrome/browser/ui/fullscreen/fullscreen_controller.h"
 #import "ios/chrome/browser/ui/overlays/overlay_container_view_controller.h"
 #import "ios/chrome/browser/ui/overlays/overlay_presentation_context_impl.h"
 #import "ios/chrome/common/ui_util/constraints_ui_util.h"
@@ -22,67 +18,8 @@
 #error "This file requires ARC support."
 #endif
 
-namespace {
-// Observer that disables fullscreen while overlays are presented.
-class OverlayContainerFullscreenDisabler {
- public:
-  OverlayContainerFullscreenDisabler(Browser* browser, OverlayModality modality)
-      : fullscreen_disabler_(
-            FullscreenController::FromBrowserState(browser->GetBrowserState()),
-            OverlayPresenter::FromBrowser(browser, modality)) {}
-  ~OverlayContainerFullscreenDisabler() = default;
-  OverlayContainerFullscreenDisabler(
-      OverlayContainerFullscreenDisabler& disabler) = delete;
-
- private:
-  // Helper object that disables fullscreen when overlays are presented.
-  class FullscreenDisabler : public OverlayPresenterObserver {
-   public:
-    FullscreenDisabler(FullscreenController* fullscreen_controller,
-                       OverlayPresenter* overlay_presenter)
-        : fullscreen_controller_(fullscreen_controller),
-          scoped_observer_(this) {
-      DCHECK(fullscreen_controller_);
-      DCHECK(overlay_presenter);
-      scoped_observer_.Add(overlay_presenter);
-    }
-    ~FullscreenDisabler() override = default;
-
-   private:
-    // OverlayPresenterObserver:
-    void WillShowOverlay(OverlayPresenter* presenter,
-                         OverlayRequest* request) override {
-      disabler_ = std::make_unique<AnimatedScopedFullscreenDisabler>(
-          fullscreen_controller_);
-      disabler_->StartAnimation();
-    }
-
-    void DidHideOverlay(OverlayPresenter* presenter,
-                        OverlayRequest* request) override {
-      disabler_ = nullptr;
-    }
-
-    void OverlayPresenterDestroyed(OverlayPresenter* presenter) override {
-      scoped_observer_.Remove(presenter);
-      disabler_ = nullptr;
-    }
-
-    // The FullscreenController being disabled.
-    FullscreenController* fullscreen_controller_ = nullptr;
-    // The animated disabler.
-    std::unique_ptr<AnimatedScopedFullscreenDisabler> disabler_;
-    ScopedObserver<OverlayPresenter, OverlayPresenterObserver> scoped_observer_;
-  };
-
-  FullscreenDisabler fullscreen_disabler_;
-};
-}  // namespace
-
 @interface OverlayContainerCoordinator () <
-    OverlayContainerViewControllerDelegate> {
-  // Helper object that disables fullscreen whenever an overlay is presented.
-  std::unique_ptr<OverlayContainerFullscreenDisabler> fullscreen_disabler_;
-}
+    OverlayContainerViewControllerDelegate>
 // Whether the coordinator is started.
 @property(nonatomic, assign, getter=isStarted) BOOL started;
 // The presentation context used by OverlayPresenter to drive presentation for
@@ -131,8 +68,6 @@ class OverlayContainerFullscreenDisabler {
   AddSameConstraints(containerView, self.baseViewController.view);
   [_viewController didMoveToParentViewController:self.baseViewController];
   self.presentationContext->SetCoordinator(self);
-  fullscreen_disabler_ = std::make_unique<OverlayContainerFullscreenDisabler>(
-      self.browser, self.modality);
 }
 
 - (void)stop {
@@ -145,7 +80,6 @@ class OverlayContainerFullscreenDisabler {
   [_viewController.view removeFromSuperview];
   [_viewController removeFromParentViewController];
   _viewController = nil;
-  fullscreen_disabler_ = nullptr;
 }
 
 #pragma mark - OverlayContainerViewControllerDelegate

ios/chrome/browser/ui/overlays/overlay_presentation_context_fullscreen_disabler.h

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef IOS_CHROME_BROWSER_UI_OVERLAYS_OVERLAY_PRESENTATION_CONTEXT_FULLSCREEN_DISABLER_H_
+#define IOS_CHROME_BROWSER_UI_OVERLAYS_OVERLAY_PRESENTATION_CONTEXT_FULLSCREEN_DISABLER_H_
+
+#include <memory>
+
+#include "base/scoped_observer.h"
+#import "ios/chrome/browser/overlays/public/overlay_modality.h"
+#import "ios/chrome/browser/overlays/public/overlay_presenter.h"
+#import "ios/chrome/browser/overlays/public/overlay_presenter_observer.h"
+
+class Browser;
+class AnimatedScopedFullscreenDisabler;
+class FullscreenController;
+
+// A helper object that disables fullscreen while overlays are displayed.
+class OverlayContainerFullscreenDisabler {
+ public:
+  // Constructs a OverlayContainerFullscreenDisabler that disables fullscreen
+  // for |browser| when overlays are displayed at |modality|.
+  OverlayContainerFullscreenDisabler(Browser* browser,
+                                     OverlayModality modality);
+  ~OverlayContainerFullscreenDisabler();
+  OverlayContainerFullscreenDisabler(
+      OverlayContainerFullscreenDisabler& disabler) = delete;
+
+ private:
+  // Helper object that disables fullscreen when overlays are presented.
+  class FullscreenDisabler : public OverlayPresenterObserver {
+   public:
+    FullscreenDisabler(FullscreenController* fullscreen_controller,
+                       OverlayPresenter* overlay_presenter);
+    ~FullscreenDisabler() override;
+
+   private:
+    // OverlayPresenterObserver:
+    void WillShowOverlay(OverlayPresenter* presenter,
+                         OverlayRequest* request) override;
+    void DidHideOverlay(OverlayPresenter* presenter,
+                        OverlayRequest* request) override;
+    void OverlayPresenterDestroyed(OverlayPresenter* presenter) override;
+
+    // The FullscreenController being disabled.
+    FullscreenController* fullscreen_controller_ = nullptr;
+    // The animated disabler.
+    std::unique_ptr<AnimatedScopedFullscreenDisabler> disabler_;
+    ScopedObserver<OverlayPresenter, OverlayPresenterObserver> scoped_observer_;
+  };
+
+  FullscreenDisabler fullscreen_disabler_;
+};
+
+#endif  // IOS_CHROME_BROWSER_UI_OVERLAYS_OVERLAY_PRESENTATION_CONTEXT_FULLSCREEN_DISABLER_H_

ios/chrome/browser/ui/overlays/overlay_presentation_context_fullscreen_disabler.mm

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import "ios/chrome/browser/ui/overlays/overlay_presentation_context_fullscreen_disabler.h"
+
+#include "base/logging.h"
+#import "ios/chrome/browser/main/browser.h"
+#import "ios/chrome/browser/ui/fullscreen/animated_scoped_fullscreen_disabler.h"
+#import "ios/chrome/browser/ui/fullscreen/fullscreen_controller.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+#pragma mark - OverlayContainerFullscreenDisabler
+
+OverlayContainerFullscreenDisabler::OverlayContainerFullscreenDisabler(
+    Browser* browser,
+    OverlayModality modality)
+    : fullscreen_disabler_(
+          FullscreenController::FromBrowserState(browser->GetBrowserState()),
+          OverlayPresenter::FromBrowser(browser, modality)) {}
+
+OverlayContainerFullscreenDisabler::~OverlayContainerFullscreenDisabler() =
+    default;
+
+#pragma mark - OverlayContainerFullscreenDisabler::FullscreenDisabler
+
+OverlayContainerFullscreenDisabler::FullscreenDisabler::FullscreenDisabler(
+    FullscreenController* fullscreen_controller,
+    OverlayPresenter* overlay_presenter)
+    : fullscreen_controller_(fullscreen_controller), scoped_observer_(this) {
+  DCHECK(fullscreen_controller_);
+  DCHECK(overlay_presenter);
+  scoped_observer_.Add(overlay_presenter);
+}
+
+OverlayContainerFullscreenDisabler::FullscreenDisabler::~FullscreenDisabler() =
+    default;
+
+void OverlayContainerFullscreenDisabler::FullscreenDisabler::WillShowOverlay(
+    OverlayPresenter* presenter,
+    OverlayRequest* request) {
+  disabler_ = std::make_unique<AnimatedScopedFullscreenDisabler>(
+      fullscreen_controller_);
+  disabler_->StartAnimation();
+}
+
+void OverlayContainerFullscreenDisabler::FullscreenDisabler::DidHideOverlay(
+    OverlayPresenter* presenter,
+    OverlayRequest* request) {
+  disabler_ = nullptr;
+}
+
+void OverlayContainerFullscreenDisabler::FullscreenDisabler::
+    OverlayPresenterDestroyed(OverlayPresenter* presenter) {
+  scoped_observer_.Remove(presenter);
+  disabler_ = nullptr;
+}

ios/chrome/browser/ui/overlays/overlay_presentation_context_fullscreen_disabler_unittest.mm

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import "ios/chrome/browser/ui/overlays/overlay_presentation_context_fullscreen_disabler.h"
+
+#import "ios/chrome/browser/main/test_browser.h"
+#include "ios/chrome/browser/overlays/public/overlay_request.h"
+#include "ios/chrome/browser/overlays/public/overlay_request_queue.h"
+#include "ios/chrome/browser/overlays/test/fake_overlay_presentation_context.h"
+#include "ios/chrome/browser/overlays/test/overlay_test_macros.h"
+#import "ios/chrome/browser/ui/fullscreen/fullscreen_controller.h"
+#import "ios/chrome/browser/web_state_list/web_state_list.h"
+#import "ios/chrome/browser/web_state_list/web_state_opener.h"
+#import "ios/web/public/test/fakes/test_web_state.h"
+#include "ios/web/public/test/web_task_environment.h"
+#include "testing/platform_test.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+namespace {
+// The modality used in tests.
+const OverlayModality kModality = OverlayModality::kWebContentArea;
+// Request config used in tests.
+DEFINE_TEST_OVERLAY_REQUEST_CONFIG(kConfig);
+}  // namespace
+
+// Test fixture for OverlayPresentationContextFullscreenDisabler.
+class OverlayPresentationContextFullscreenDisablerTest : public PlatformTest {
+ public:
+  OverlayPresentationContextFullscreenDisablerTest()
+      : disabler_(&browser_, kModality) {
+    // Set up the fake presentation context so OverlayPresenterObserver
+    // callbacks are sent.
+    overlay_presenter()->SetPresentationContext(&presentation_context_);
+    // Insert and activate a WebState.
+    browser_.GetWebStateList()->InsertWebState(
+        0, std::make_unique<web::TestWebState>(), WebStateList::INSERT_ACTIVATE,
+        WebStateOpener());
+  }
+  ~OverlayPresentationContextFullscreenDisablerTest() override {
+    overlay_presenter()->SetPresentationContext(nullptr);
+  }
+
+  bool fullscreen_enabled() {
+    return FullscreenController::FromBrowserState(browser_.GetBrowserState())
+        ->IsEnabled();
+  }
+  OverlayPresenter* overlay_presenter() {
+    return OverlayPresenter::FromBrowser(&browser_, kModality);
+  }
+  OverlayRequestQueue* queue() {
+    return OverlayRequestQueue::FromWebState(
+        browser_.GetWebStateList()->GetActiveWebState(), kModality);
+  }
+
+ protected:
+  web::WebTaskEnvironment task_environment_;
+  TestBrowser browser_;
+  OverlayContainerFullscreenDisabler disabler_;
+  FakeOverlayPresentationContext presentation_context_;
+};
+
+// Tests that OverlayPresentationContextFullscreenDisabler disables fullscreen
+// when overlays are displayed.
+TEST_F(OverlayPresentationContextFullscreenDisablerTest,
+       DisableForPresentedOverlays) {
+  ASSERT_TRUE(fullscreen_enabled());
+
+  // Add an OverlayRequest to the active WebState's queue and verify that
+  // fullscreen is disabled.
+  queue()->AddRequest(OverlayRequest::CreateWithConfig<kConfig>());
+  EXPECT_FALSE(fullscreen_enabled());
+
+  // Cancel the request and verify that fullscreen is re-enabled.
+  queue()->CancelAllRequests();
+  EXPECT_TRUE(fullscreen_enabled());
+}

ios/chrome/browser/ui/overlays/overlay_presentation_context_impl.h

@@ -11,6 +11,7 @@
 #include "ios/chrome/browser/overlays/public/overlay_modality.h"
 #import "ios/chrome/browser/overlays/public/overlay_presentation_context.h"
 #import "ios/chrome/browser/overlays/public/overlay_user_data.h"
+#import "ios/chrome/browser/ui/overlays/overlay_presentation_context_fullscreen_disabler.h"
 #import "ios/chrome/browser/ui/overlays/overlay_request_coordinator.h"
 #import "ios/chrome/browser/ui/overlays/overlay_request_coordinator_delegate.h"
 #import "ios/chrome/browser/ui/overlays/overlay_request_ui_state.h"
@@ -139,6 +140,8 @@ class OverlayPresentationContextImpl : public OverlayPresentationContext {
   // The delegate used to intercept presentation/dismissal events from
   // OverlayRequestCoordinators.
   OverlayRequestCoordinatorDelegateImpl coordinator_delegate_;
+  // The fullscreen disabler helper.
+  OverlayContainerFullscreenDisabler fullscreen_disabler_;
   // The coordinator factory that provides the UI for the overlays at this
   // modality.
   OverlayRequestCoordinatorFactory* coordinator_factory_ = nil;

ios/chrome/browser/ui/overlays/overlay_presentation_context_impl.mm

@@ -48,6 +48,7 @@ OverlayPresentationContextImpl::OverlayPresentationContextImpl(
     : presenter_(OverlayPresenter::FromBrowser(browser, modality)),
       shutdown_helper_(browser, presenter_),
       coordinator_delegate_(this),
+      fullscreen_disabler_(browser, modality),
       coordinator_factory_([OverlayRequestCoordinatorFactory
           factoryForBrowser:browser
                    modality:modality]),