Refactor in app to home nudge logic.

Moving logic out of shelf_layout_manager and into a separate controller class.

Tests for this behavior are in shelf_drag_handle_unittest.cc: will be refactored into
in_app_to_home_nudge_controller_unittest.cc in a follow up CL.

Bug: 1062690
Change-Id: Icb44ddcec0a89be131132723d4db0735a4e50825
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2152953Reviewed-by: Yulun Wu <yulunwu@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: Alex Newcomer <newcomer@chromium.org>
Commit-Queue: Yulun Wu <yulunwu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#760131}

ash/BUILD.gn

@@ -641,6 +641,8 @@ component("ash") {
     "shelf/hotseat_transition_animator.h",
     "shelf/hotseat_widget.cc",
     "shelf/hotseat_widget.h",
+    "shelf/in_app_to_home_nudge_controller.cc",
+    "shelf/in_app_to_home_nudge_controller.h",
     "shelf/login_shelf_gesture_controller.cc",
     "shelf/login_shelf_gesture_controller.h",
     "shelf/login_shelf_view.cc",

ash/shelf/in_app_to_home_nudge_controller.cc

+// 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.
+
+#include "ash/shelf/in_app_to_home_nudge_controller.h"
+
+#include "ash/session/session_controller_impl.h"
+#include "ash/shelf/drag_handle.h"
+#include "ash/shelf/shelf_widget.h"
+#include "ash/shell.h"
+
+namespace ash {
+
+InAppToHomeNudgeController::InAppToHomeNudgeController(
+    ShelfWidget* shelf_widget)
+    : shelf_widget_(shelf_widget) {}
+
+InAppToHomeNudgeController::~InAppToHomeNudgeController() = default;
+
+void InAppToHomeNudgeController::SetNudgeAllowedForCurrentShelf(
+    bool in_tablet_mode,
+    bool in_app_shelf) {
+  if (in_tablet_mode && in_app_shelf) {
+    if (contextual_tooltip::ShouldShowNudge(
+            Shell::Get()->session_controller()->GetLastActiveUserPrefService(),
+            contextual_tooltip::TooltipType::kInAppToHome,
+            /*recheck_delay*/ nullptr)) {
+      shelf_widget_->ScheduleShowDragHandleNudge();
+    } else if (!shelf_widget_->GetDragHandle()
+                    ->gesture_nudge_target_visibility()) {
+      // If the drag handle is not yet shown, HideDragHandleNudge() should
+      // cancel any scheduled show requests.
+      shelf_widget_->HideDragHandleNudge(
+          contextual_tooltip::DismissNudgeReason::kOther);
+    }
+  } else {
+    shelf_widget_->HideDragHandleNudge(
+        in_tablet_mode
+            ? contextual_tooltip::DismissNudgeReason::kExitToHomeScreen
+            : contextual_tooltip::DismissNudgeReason::kSwitchToClamshell);
+  }
+}
+
+}  // namespace ash

ash/shelf/in_app_to_home_nudge_controller.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 ASH_SHELF_IN_APP_TO_HOME_NUDGE_CONTROLLER_H_
+#define ASH_SHELF_IN_APP_TO_HOME_NUDGE_CONTROLLER_H_
+
+#include "ash/ash_export.h"
+
+namespace ash {
+
+class ShelfWidget;
+
+// Used by Chrome to notify shelf status changes and update in app to home
+// gesture contextual nudge UI.
+class ASH_EXPORT InAppToHomeNudgeController {
+ public:
+  explicit InAppToHomeNudgeController(ShelfWidget* shelf_widget);
+  InAppToHomeNudgeController(const InAppToHomeNudgeController&) = delete;
+  InAppToHomeNudgeController& operator=(const InAppToHomeNudgeController&) =
+      delete;
+  ~InAppToHomeNudgeController();
+
+  // Sets whether the in app to home nudge can be shown for the current shelf
+  // state. If the nudge is allowed, controller may show the nudge if required.
+  // If the nudge is not allowed, the nudge will be hidden if currently visible.
+  void SetNudgeAllowedForCurrentShelf(bool in_tablet_mode, bool in_app_shelf);
+
+ private:
+  // pointer to the shelf widget that owns the drag handle anchoring the nudge.
+  ShelfWidget* const shelf_widget_;
+};
+
+}  // namespace ash
+
+#endif  // ASH_SHELF_IN_APP_TO_HOME_NUDGE_CONTROLLER_H_

ash/shelf/shelf_layout_manager.cc

@@ -30,6 +30,7 @@
 #include "ash/shelf/drag_handle.h"
 #include "ash/shelf/home_to_overview_nudge_controller.h"
 #include "ash/shelf/hotseat_widget.h"
+#include "ash/shelf/in_app_to_home_nudge_controller.h"
 #include "ash/shelf/shelf.h"
 #include "ash/shelf/shelf_layout_manager_observer.h"
 #include "ash/shelf/shelf_metrics.h"
@@ -612,23 +613,14 @@ void ShelfLayoutManager::UpdateContextualNudges() {
 
   contextual_tooltip::SetDragHandleNudgeDisabledForHiddenShelf(!IsVisible());
 
-  if (in_app_shelf && in_tablet_mode) {
-    if (contextual_tooltip::ShouldShowNudge(
-            Shell::Get()->session_controller()->GetLastActiveUserPrefService(),
-            contextual_tooltip::TooltipType::kInAppToHome, nullptr)) {
-      shelf_widget_->ScheduleShowDragHandleNudge();
-    } else if (!shelf_widget_->GetDragHandle()
-                    ->gesture_nudge_target_visibility()) {
-      // If the drag handle is not yet shown, HideDragHandleNudge() should
-      // cancel any scheduled show requests.
-      shelf_widget_->HideDragHandleNudge(
-          contextual_tooltip::DismissNudgeReason::kOther);
-    }
-  } else {
-    shelf_widget_->HideDragHandleNudge(
-        in_tablet_mode
-            ? contextual_tooltip::DismissNudgeReason::kExitToHomeScreen
-            : contextual_tooltip::DismissNudgeReason::kSwitchToClamshell);
+  if (in_app_shelf && in_tablet_mode && !in_app_to_home_nudge_controller_) {
+    in_app_to_home_nudge_controller_ =
+        std::make_unique<InAppToHomeNudgeController>(shelf_widget_);
+  }
+
+  if (in_app_to_home_nudge_controller_) {
+    in_app_to_home_nudge_controller_->SetNudgeAllowedForCurrentShelf(
+        in_tablet_mode, in_app_shelf);
   }
 
   // Create home to overview nudge controller if home to overview nudge is

ash/shelf/shelf_layout_manager.h

@@ -54,6 +54,7 @@ namespace ash {
 enum class AnimationChangeType;
 class DragWindowFromShelfController;
 class HomeToOverviewNudgeController;
+class InAppToHomeNudgeController;
 class PanelLayoutManagerTest;
 class PresentationTimeRecorder;
 class Shelf;
@@ -636,6 +637,9 @@ class ASH_EXPORT ShelfLayoutManager
   std::unique_ptr<HomeToOverviewNudgeController>
       home_to_overview_nudge_controller_;
 
+  // Controller for the visibility of the InAppToHome gesture contextual nudge.
+  std::unique_ptr<InAppToHomeNudgeController> in_app_to_home_nudge_controller_;
+
   // Whether upward fling from shelf should be handled as potential gesture from
   // overview to home. This is set when the swipe would otherwise be handled by
   // |window_drag_controller_|, but the swipe cannot be associated with a window