Do nothing on OnSessionStopped if ARC is being restarted.

components/arc/arc_session.cc

Index: components/arc/arc_session.cc
diff --git a/components/arc/arc_session.cc b/components/arc/arc_session.cc
index c063a64574273278a690b13e2d8c49e40426f0a0..c369d28c9c4e8c1501e9ced66c5270959a20463b 100644
--- a/components/arc/arc_session.cc
+++ b/components/arc/arc_session.cc
@@ -28,7 +28,6 @@
 #include "chromeos/dbus/session_manager_client.h"
 #include "components/arc/arc_bridge_host_impl.h"
 #include "components/arc/arc_features.h"
-#include "components/arc/arc_session_observer.h"
 #include "components/user_manager/user_manager.h"
 #include "mojo/edk/embedder/embedder.h"
 #include "mojo/edk/embedder/named_platform_handle.h"
@@ -127,7 +126,7 @@ class ArcSessionImpl : public ArcSession,
   //
   // At any state, Stop() can be called. It does not immediately stop the
   // instance, but will eventually stop it.
-  // The actual stop will be notified via ArcSessionObserver::OnStopped().
+  // The actual stop will be notified via ArcSession::Observer::OnStopped().
   //
   // When Stop() is called, it makes various behavior based on the current
   // phase.
@@ -235,7 +234,7 @@ class ArcSessionImpl : public ArcSession,
   void ArcInstanceStopped(bool clean) override;
 
   // Completes the termination procedure.
-  void OnStopped(ArcSessionObserver::StopReason reason);
+  void OnStopped(ArcStopReason reason);
 
   // Checks whether a function runs on the thread where the instance is
   // created.
@@ -346,13 +345,13 @@ void ArcSessionImpl::OnSocketCreated(
 
   if (stop_requested_) {
     VLOG(1) << "Stop() called while connecting";
-    OnStopped(ArcSessionObserver::StopReason::SHUTDOWN);
+    OnStopped(ArcStopReason::SHUTDOWN);
     return;
   }
 
   if (!socket_fd.is_valid()) {
     LOG(ERROR) << "ARC: Error creating socket";
-    OnStopped(ArcSessionObserver::StopReason::GENERIC_BOOT_FAILURE);
+    OnStopped(ArcStopReason::GENERIC_BOOT_FAILURE);
     return;
   }
 
@@ -393,15 +392,15 @@ void ArcSessionImpl::OnInstanceStarted(
       StopArcInstance();
       return;
     }
-    OnStopped(ArcSessionObserver::StopReason::SHUTDOWN);
+    OnStopped(ArcStopReason::SHUTDOWN);
     return;
   }
 
   if (result != StartArcInstanceResult::SUCCESS) {
     LOG(ERROR) << "Failed to start ARC instance";
     OnStopped(result == StartArcInstanceResult::LOW_FREE_DISK_SPACE
-                  ? ArcSessionObserver::StopReason::LOW_DISK_SPACE
-                  : ArcSessionObserver::StopReason::GENERIC_BOOT_FAILURE);
+                  ? ArcStopReason::LOW_DISK_SPACE
+                  : ArcStopReason::GENERIC_BOOT_FAILURE);
     return;
   }
 
@@ -412,7 +411,7 @@ void ArcSessionImpl::OnInstanceStarted(
   // Stop().
   base::ScopedFD cancel_fd;
   if (!CreatePipe(&cancel_fd, &accept_cancel_pipe_)) {
-    OnStopped(ArcSessionObserver::StopReason::GENERIC_BOOT_FAILURE);
+    OnStopped(ArcStopReason::GENERIC_BOOT_FAILURE);
     return;
   }
 
@@ -519,7 +518,7 @@ void ArcSessionImpl::Stop() {
   arc_bridge_host_.reset();
   switch (state_) {
     case State::NOT_STARTED:
-      OnStopped(ArcSessionObserver::StopReason::SHUTDOWN);
+      OnStopped(ArcStopReason::SHUTDOWN);
       return;
 
     case State::CREATING_SOCKET:
@@ -576,24 +575,24 @@ void ArcSessionImpl::ArcInstanceStopped(bool clean) {
   // unlock the BlockingPool thread.
   accept_cancel_pipe_.reset();
 
-  ArcSessionObserver::StopReason reason;
+  ArcStopReason reason;
   if (stop_requested_) {
     // If the ARC instance is stopped after its explicit request,
     // return SHUTDOWN.
-    reason = ArcSessionObserver::StopReason::SHUTDOWN;
+    reason = ArcStopReason::SHUTDOWN;
   } else if (clean) {
     // If the ARC instance is stopped, but it is not explicitly requested,
     // then this is triggered by some failure during the starting procedure.
     // Return GENERIC_BOOT_FAILURE for the case.
-    reason = ArcSessionObserver::StopReason::GENERIC_BOOT_FAILURE;
+    reason = ArcStopReason::GENERIC_BOOT_FAILURE;
   } else {
     // Otherwise, this is caused by CRASH occured inside of the ARC instance.
-    reason = ArcSessionObserver::StopReason::CRASH;
+    reason = ArcStopReason::CRASH;
   }
   OnStopped(reason);
 }
 
-void ArcSessionImpl::OnStopped(ArcSessionObserver::StopReason reason) {
+void ArcSessionImpl::OnStopped(ArcStopReason reason) {
   DCHECK(thread_checker_.CalledOnValidThread());
   // OnStopped() should be called once per instance.
   DCHECK_NE(state_, State::STOPPED);
@@ -626,7 +625,7 @@ void ArcSessionImpl::OnShutdown() {
   // Directly set to the STOPPED stateby OnStopped(). Note that calling
   // StopArcInstance() may not work well. At least, because the UI thread is
   // already stopped here, ArcInstanceStopped() callback cannot be invoked.
-  OnStopped(ArcSessionObserver::StopReason::SHUTDOWN);
+  OnStopped(ArcStopReason::SHUTDOWN);
 }
 
 }  // namespace
@@ -634,11 +633,11 @@ void ArcSessionImpl::OnShutdown() {
 ArcSession::ArcSession() = default;
 ArcSession::~ArcSession() = default;
 
-void ArcSession::AddObserver(ArcSessionObserver* observer) {
+void ArcSession::AddObserver(Observer* observer) {
   observer_list_.AddObserver(observer);
 }
 
-void ArcSession::RemoveObserver(ArcSessionObserver* observer) {
+void ArcSession::RemoveObserver(Observer* observer) {
   observer_list_.RemoveObserver(observer);
 }