Fixes shutdown race in mash

Fixes shutdown race in mash

Prior to this change it was possible for the AcceleratorRegistrarImpl
to outlive the WindowManager and then attempt to use it. This patch
ensures any AcceleratorRegistrarImpl are destroyed when the
WindowManager loses its connection.

BUG=none
TEST=none
R=ben@chromium.org

Committed: https://crrev.com/df7885ca3b786414ec9a9f9899a7bd24884c4126
Cr-Commit-Position: refs/heads/master@{#402670}

[Ben Goodger (Google), 2016-06-28 21:28:08]

lgtm

[sky, 2016-06-28 21:35:24]

The CQ bit was checked by sky@chromium.org

[commit-bot: I haz the power, 2016-06-28 21:37:08]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-06-28 23:07:05]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-06-28 23:07:09]

Failed to apply patch for ash/mus/window_manager_application.cc:
While running git apply --index -3 -p1;
  error: patch failed: ash/mus/window_manager_application.cc:60
  Falling back to three-way merge...
  Applied patch to 'ash/mus/window_manager_application.cc' with conflicts.
  U ash/mus/window_manager_application.cc

Patch:       ash/mus/window_manager_application.cc
Index: ash/mus/window_manager_application.cc
diff --git a/ash/mus/window_manager_application.cc
b/ash/mus/window_manager_application.cc
index
a6b85afd2f6b349311765f0afabfe852d8e93acf..a1d4edc7834c0602e77817576c8306192c1a3b9f
100644
--- a/ash/mus/window_manager_application.cc
+++ b/ash/mus/window_manager_application.cc
@@ -8,7 +8,6 @@
 
 #include "ash/mus/accelerator_registrar_impl.h"
 #include "ash/mus/root_window_controller.h"
-#include "ash/mus/root_windows_observer.h"
 #include "ash/mus/shelf_layout_impl.h"
 #include "ash/mus/user_window_controller_impl.h"
 #include "ash/mus/window_manager.h"
@@ -42,16 +41,6 @@ WindowManagerApplication::~WindowManagerApplication() {
   window_manager_.reset();
 }
 
-void WindowManagerApplication::OnAccelerator(uint32_t id,
-                                             const ui::Event& event) {
-  for (auto* registrar : accelerator_registrars_) {
-    if (registrar->OwnsAccelerator(id)) {
-      registrar->ProcessAccelerator(id, event);
-      break;
-    }
-  }
-}
-
 void WindowManagerApplication::OnAcceleratorRegistrarDestroyed(
     AcceleratorRegistrarImpl* registrar) {
   accelerator_registrars_.erase(registrar);
@@ -60,14 +49,14 @@ void
WindowManagerApplication::OnAcceleratorRegistrarDestroyed(
 void WindowManagerApplication::InitWindowManager(
     ::mus::WindowTreeClient* window_tree_client) {
   window_manager_->Init(window_tree_client);
-  window_manager_->AddRootWindowsObserver(this);
+  window_manager_->AddObserver(this);
 }
 
 void WindowManagerApplication::Initialize(shell::Connector* connector,
                                           const shell::Identity& identity,
                                           uint32_t id) {
   connector_ = connector;
-  window_manager_.reset(new WindowManager(this, connector_));
+  window_manager_.reset(new WindowManager(connector_));
 
   aura_init_.reset(new views::AuraInit(connector_, "ash_mus_resources.pak"));
 
@@ -120,6 +109,9 @@ void WindowManagerApplication::Create(
 void WindowManagerApplication::Create(
     shell::Connection* connection,
     mojo::InterfaceRequest<::mus::mojom::AcceleratorRegistrar> request) {
+  if (!window_manager_->window_manager_client())
+    return;  // Can happen during shutdown.
+
   static int accelerator_registrar_count = 0;
   if (accelerator_registrar_count == std::numeric_limits<int>::max()) {
     // Restart from zero if we have reached the limit. It is technically

[sky, 2016-06-28 23:12:58]

The CQ bit was checked by sky@chromium.org

[sky, 2016-06-28 23:12:58]

The patchset sent to the CQ was uploaded after l-g-t-m from ben@chromium.org
Link to the patchset: https://codereview.chromium.org/2105653003/#ps20001
(title: "merge")

[commit-bot: I haz the power, 2016-06-28 23:14:33]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-06-29 02:24:30]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-06-29 02:26:10]

Description was changed from

==========
Fixes shutdown race in mash

Prior to this change it was possible for the AcceleratorRegistrarImpl
to outlive the WindowManager and then attempt to use it. This patch
ensures any AcceleratorRegistrarImpl are destroyed when the
WindowManager loses its connection.

BUG=none
TEST=none
R=ben@chromium.org
==========

to

==========
Fixes shutdown race in mash

Prior to this change it was possible for the AcceleratorRegistrarImpl
to outlive the WindowManager and then attempt to use it. This patch
ensures any AcceleratorRegistrarImpl are destroyed when the
WindowManager loses its connection.

BUG=none
TEST=none
R=ben@chromium.org

Committed: https://crrev.com/df7885ca3b786414ec9a9f9899a7bd24884c4126
Cr-Commit-Position: refs/heads/master@{#402670}
==========

[commit-bot: I haz the power, 2016-06-29 02:26:12]

Patchset 2 (id:??) landed as
https://crrev.com/df7885ca3b786414ec9a9f9899a7bd24884c4126
Cr-Commit-Position: refs/heads/master@{#402670}