arc: Notify ARC instance failures via callbacks.

components/arc/arc_bridge_service.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_ARC_ARC_BRIDGE_SERVICE_H_
 #define COMPONENTS_ARC_ARC_BRIDGE_SERVICE_H_
 
 #include <string>
 #include <vector>
 
 #include "base/files/scoped_file.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/observer_list.h"
 #include "base/values.h"
 #include "components/arc/common/arc_bridge.mojom.h"
 
 namespace base {
 class CommandLine;
 }  // namespace base
 
 namespace arc {
 
-class ArcBridgeBootstrap;
-
 // The Chrome-side service that handles ARC instances and ARC bridge creation.
 // This service handles the lifetime of ARC instances and sets up the
 // communication channel (the ARC bridge) used to send and receive messages.
 class ArcBridgeService : public mojom::ArcBridgeHost {
  public:
   // The possible states of the bridge.  In the normal flow, the state changes
   // in the following sequence:
   //
   // STOPPED
   //   PrerequisitesChanged() ->
@@ skipping 20 matching lines @@
     CONNECTED,
 
     // The ARC instance has finished initializing and is now ready for user
     // interaction.
     READY,
 
     // The ARC instance has started shutting down.
     STOPPING,
   };
 
+  // Describes the reason the bridge is being aborted.
+  enum class AbortReason {
+    // ARC instance boot failed for unknown errors.

[Luis Héctor Chávez, 2016/07/08 18:01:02]

nit: it's better to say that this is just any error that happens during the
setup before the instance is actually attempted to be started.

[Shuhei Takahashi, 2016/07/11 08:25:19]

Thanks, I've updated the comment. Does it look good to you?

[Luis Héctor Chávez, 2016/07/11 22:28:50]

It does, thanks!

+    GENERIC_BOOT_FAILURE,
+
+    // ARC instance has crashed.
+    CRASH,
+  };
+
   // Notifies life cycle events of ArcBridgeService.
   class Observer {
    public:
     // Called whenever the state of the bridge has changed.
     // TODO(lchavez): Rename to OnStateChangedForTest
     virtual void OnStateChanged(State state) {}
+
+    // Called whenever the bridge got ready.

[Luis Héctor Chávez, 2016/07/08 18:01:02]

nit: the bridge is ready.

[Shuhei Takahashi, 2016/07/11 08:25:19]

Done.

     virtual void OnBridgeReady() {}
+
+    // Called whenever the bridge is being aborted due to errors.
+    // After this callback is invoked, the ARC instance will be stopped, so
+    // you do not need to call ArcBridgeServiceImpl::StopInstance() in the
+    // callback.
+    virtual void OnBridgeAborting(AbortReason reason) {}
+
+    // Called whenever the bridge stopped.

[Luis Héctor Chávez, 2016/07/08 18:01:02]

nit: the bridge is stopped.

[Shuhei Takahashi, 2016/07/11 08:25:19]

Done.

+    // When the bridge aborted due to errors, OnBridgeAborting() is called
+    // first, then OnBridgeStopped() is called once the instance is stopped.
     virtual void OnBridgeStopped() {}
 
     // Called whenever ARC's availability has changed for this system.
     virtual void OnAvailableChanged(bool available) {}
 
     // Called whenever the ARC app interface state changes.
     virtual void OnAppInstanceReady() {}
     virtual void OnAppInstanceClosed() {}
 
     // Called whenever the ARC audio interface state changes.
@@ skipping 330 matching lines @@
 
   // WeakPtrFactory to use callbacks.
   base::WeakPtrFactory<ArcBridgeService> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ArcBridgeService);
 };
 
 }  // namespace arc
 
 #endif  // COMPONENTS_ARC_ARC_BRIDGE_SERVICE_H_