float: Fix some tests that fail when feature is enabled p2.

RootWindowControllerTest.DontDeleteWindowsNotOwnedByParent fails if
dangling raw pointer checks are enabled. It is because float
containers workspace event handler is not removed at the same time
as the others.

After this is test is fixed, we can enable the feature flag.

Bug: b/275562398
Test: existing tests
Change-Id: I8dc8c172fa0d38429f330502257d152dfaa1bd7a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4024210
Commit-Queue: Sammie Quon <sammiequon@chromium.org>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1123298}

ash/root_window_controller.cc

@@ -57,6 +57,7 @@
 #include "ash/wm/container_finder.h"
 #include "ash/wm/desks/desks_controller.h"
 #include "ash/wm/desks/desks_util.h"
+#include "ash/wm/float/float_controller.h"
 #include "ash/wm/fullscreen_window_finder.h"
 #include "ash/wm/lock_action_handler_layout_manager.h"
 #include "ash/wm/lock_layout_manager.h"
@@ -338,6 +339,9 @@ void ClearWorkspaceControllers(aura::Window* root) {
   for (auto* desk_container : desks_util::GetDesksContainers(root)) {
     SetWorkspaceController(desk_container, nullptr);
   }
+  if (auto* float_controller = Shell::Get()->float_controller()) {
+    float_controller->ClearWorkspaceEventHandler(root);
+  }
 }
 
 class RootWindowTargeter : public aura::WindowTargeter {

ash/wm/float/float_controller.cc

@@ -632,6 +632,10 @@ void FloatController::OnMovingFloatedWindowToDesk(aura::Window* floated_window,
   target_desk->NotifyContentChanged();
 }
 
+void FloatController::ClearWorkspaceEventHandler(aura::Window* root) {
+  workspace_event_handlers_.erase(root);
+}
+
 void FloatController::OnTabletModeStarted() {
   DCHECK(!floated_window_info_map_.empty());
   // If a window can still remain floated, update its bounds, otherwise unfloat
@@ -724,14 +728,6 @@ void FloatController::OnRootWindowAdded(aura::Window* root_window) {
       ->SetLayoutManager(std::make_unique<FloatLayoutManager>());
 }
 
-void FloatController::OnRootWindowWillShutdown(aura::Window* root_window) {
-  workspace_event_handlers_.erase(root_window);
-}
-
-void FloatController::OnShellDestroying() {
-  workspace_event_handlers_.clear();
-}
-
 void FloatController::ToggleFloat(aura::Window* window) {
   WindowState* window_state = WindowState::Get(window);
   const WMEvent toggle_event(window_state->IsFloated() ? WM_EVENT_RESTORE

ash/wm/float/float_controller.h

@@ -114,6 +114,8 @@ class ASH_EXPORT FloatController : public TabletModeObserver,
                                    Desk* target_desk,
                                    aura::Window* target_root);
 
+  void ClearWorkspaceEventHandler(aura::Window* root);
+
   // TabletModeObserver:
   void OnTabletModeStarted() override;
   void OnTabletModeEnding() override;
@@ -129,8 +131,6 @@ class ASH_EXPORT FloatController : public TabletModeObserver,
 
   // ShellObserver:
   void OnRootWindowAdded(aura::Window* root_window) override;
-  void OnRootWindowWillShutdown(aura::Window* root_window) override;
-  void OnShellDestroying() override;
 
   // chromeos::FloatControllerBase:
   void ToggleFloat(aura::Window* window) override;