Flip feature flag to maintain shelf state on overview.

Fixed bug where home to overview nudge was not being hidden when
transitioning to overview mode. Fixed bug where
use_in_app_shelf_in_overview_ was not reset when ending overview mode.

Bug: 1123553
Change-Id: I8d00c0c685793d74ce5f813ebf3b2c8de1d7a88d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2385897Reviewed-by: Xiyuan Slow <xiyuan@chromium.org>
Reviewed-by: Yulun Wu <yulunwu@chromium.org>
Commit-Queue: Yulun Wu <yulunwu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#803918}

ash/public/cpp/ash_features.cc

@@ -131,8 +131,7 @@ const base::Feature kNotificationsInContextMenu{
     "NotificationsInContextMenu", base::FEATURE_DISABLED_BY_DEFAULT};
 
 const base::Feature kMaintainShelfStateWhenEnteringOverview{
-    "MaintainShelfStateWhenEnteringOverview",
-    base::FEATURE_DISABLED_BY_DEFAULT};
+    "MaintainShelfStateWhenEnteringOverview", base::FEATURE_ENABLED_BY_DEFAULT};
 
 const base::Feature kTemporaryHoldingSpace{"TemporaryHoldingSpace",
                                            base::FEATURE_DISABLED_BY_DEFAULT};

ash/public/cpp/shelf_config.h

@@ -185,6 +185,8 @@ class ASH_EXPORT ShelfConfig : public TabletModeObserver,
   // Opacity of the ink drop ripple for shelf items when the ripple is visible.
   float GetInkDropVisibleOpacity() const;
 
+  bool in_overview_mode() const { return overview_mode_; }
+
   // Gets the current color for the shelf control buttons.
   SkColor GetShelfControlButtonColor() const;
 

ash/shelf/shelf_config.cc

@@ -194,6 +194,7 @@ void ShelfConfig::OnOverviewModeWillStart() {
 
 void ShelfConfig::OnOverviewModeEnding(OverviewSession* overview_session) {
   overview_mode_ = false;
+  use_in_app_shelf_in_overview_ = false;
   UpdateConfig(is_app_list_visible_, /*tablet_mode_changed=*/false);
 }
 

ash/shelf/shelf_layout_manager.cc

@@ -617,6 +617,7 @@ void ShelfLayoutManager::UpdateContextualNudges() {
 
   const bool in_app_shelf = ShelfConfig::Get()->is_in_app();
   const bool in_tablet_mode = ShelfConfig::Get()->in_tablet_mode();
+  const bool in_overview_mode = ShelfConfig::Get()->in_overview_mode();
 
   contextual_tooltip::SetDragHandleNudgeDisabledForHiddenShelf(!IsVisible());
 
@@ -635,7 +636,7 @@ void ShelfLayoutManager::UpdateContextualNudges() {
   // allowed by the current shelf state.
   const bool allow_home_to_overview_nudge =
       in_tablet_mode && !in_app_shelf &&
-      !ShelfConfig::Get()->shelf_controls_shown();
+      !ShelfConfig::Get()->shelf_controls_shown() && !in_overview_mode;
   if (allow_home_to_overview_nudge && !home_to_overview_nudge_controller_) {
     home_to_overview_nudge_controller_ =
         std::make_unique<HomeToOverviewNudgeController>(
@@ -1032,6 +1033,7 @@ void ShelfLayoutManager::OnOverviewModeWillStart() {
 void ShelfLayoutManager::OnOverviewModeStarting() {
   overview_mode_will_start_ = false;
   overview_suspend_work_area_update_.emplace(this);
+  UpdateContextualNudges();
 }
 
 void ShelfLayoutManager::OnOverviewModeStartingAnimationComplete(

chrome/browser/flag-metadata.json

@@ -2972,7 +2972,7 @@
   {
     "name": "maintain-shelf-state-overview",
     "owners": [ "yulunwu" ],
-    "expiry_milestone": 86
+    "expiry_milestone": 88
   },
   {
     "name": "managed-bookmarks-ios",