Update event states in Env when target window has been destroyed.

ui/aura/mus/window_tree_client.cc

Index: ui/aura/mus/window_tree_client.cc
diff --git a/ui/aura/mus/window_tree_client.cc b/ui/aura/mus/window_tree_client.cc
index 21332451bfa77dd56112fd5ad1fe9d2b5749ece9..56333ee27b2e010fa230ab468d854dbfc9a9951f 100644
--- a/ui/aura/mus/window_tree_client.cc
+++ b/ui/aura/mus/window_tree_client.cc
@@ -29,6 +29,7 @@
 #include "ui/aura/client/drag_drop_client.h"
 #include "ui/aura/client/transient_window_client.h"
 #include "ui/aura/env.h"
+#include "ui/aura/env_input_state_controller.h"
 #include "ui/aura/mus/capture_synchronizer.h"
 #include "ui/aura/mus/drag_drop_controller_mus.h"
 #include "ui/aura/mus/focus_synchronizer.h"
@@ -46,6 +47,7 @@
 #include "ui/aura/mus/window_tree_host_mus.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_delegate.h"
+#include "ui/aura/window_event_dispatcher.h"
 #include "ui/aura/window_tracker.h"
 #include "ui/base/layout.h"
 #include "ui/base/ui_base_types.h"
@@ -1212,7 +1214,9 @@ void WindowTreeClient::OnWindowInputEvent(uint32_t event_id,
   if (event->IsKeyEvent()) {
     DCHECK(!matches_pointer_watcher);  // PointerWatcher isn't for key events.
     if (!window || !window->GetWindow()->GetHost()) {
-      tree_->OnWindowInputEventAck(event_id, ui::mojom::EventResult::UNHANDLED);
+      // Drop the |event| and not necessary to update event states as it's a
+      // key event.
+      tree_->OnWindowInputEventAck(event_id, ui::mojom::EventResult::HANDLED);

[sadrul, 2017/03/31 05:10:51]

I actually think this should be UNHANDLED. (because otherwise, if there are some
post-target accelerators, those will not be triggered).

[riajiang, 2017/03/31 21:24:03]

Right! Done.

       return;
     }
     InputMethodMus* input_method = GetWindowTreeHostMus(window)->input_method();
@@ -1229,9 +1233,30 @@ void WindowTreeClient::OnWindowInputEvent(uint32_t event_id,
                                       window ? window->GetWindow() : nullptr);
   }
 
-  // TODO: use |display_id| to find host and send there.
+  // If the window has already been deleted, use |event| to update event states
+  // kept in aura::Env and drop the |event|. Any WindowTreeHost should be okay
+  // to get aura::EnvInputStateController from since these are global states.
   if (!window || !window->GetWindow()->GetHost()) {
-    tree_->OnWindowInputEventAck(event_id, ui::mojom::EventResult::UNHANDLED);
+    DCHECK(!roots_.empty());
+    EnvInputStateController* env_controller =
+        GetWindowTreeHostMus(*roots_.begin())->dispatcher()->env_controller();
+    if (event->IsMousePointerEvent()) {
+      if (event->type() == ui::ET_POINTER_WHEEL_CHANGED) {
+        ui::MouseWheelEvent mapped_event(*event->AsPointerEvent());
+        env_controller->UpdateStateForMouseEvent(nullptr, mapped_event);
+      } else {
+        ui::MouseEvent mapped_event(*event->AsPointerEvent());
+        env_controller->UpdateStateForMouseEvent(nullptr, mapped_event);
+      }
+    } else if (event->IsMouseEvent()) {
+      env_controller->UpdateStateForMouseEvent(nullptr, *event->AsMouseEvent());
+    } else if (event->IsTouchPointerEvent()) {
+      ui::TouchEvent mapped_event(*event->AsPointerEvent());
+      env_controller->UpdateStateForTouchEvent(mapped_event);
+    } else if (event->IsTouchEvent()) {
+      env_controller->UpdateStateForTouchEvent(*event->AsTouchEvent());
+    }

[sadrul, 2017/03/31 05:10:51]

Two comments:
. We should not receive MouseEvent or TouchEvent from the window server, right?
So you shouldn't need those two cases.

. Let's move this code into
EnvInputStateController::UpdateStateForPointerEvent(), and do the necessary work
in there.

[riajiang, 2017/03/31 21:24:03]

As discussed offline, going to use the MapEvent helper function from CL
https://codereview.chromium.org/2792573003.

+    tree_->OnWindowInputEventAck(event_id, ui::mojom::EventResult::HANDLED);

[sadrul, 2017/03/31 05:10:51]

UNHANDLED.

[riajiang, 2017/03/31 21:24:03]

Done.

     return;
   }