Device Service: Decouple Wake Lock from //content

device/wake_lock/wake_lock_service_context.h

Index: device/wake_lock/wake_lock_service_context.h
diff --git a/device/wake_lock/wake_lock_service_context.h b/device/wake_lock/wake_lock_service_context.h
index 01e7ebef29d1c6df794266af38e405b3ef41176d..28f14d761611d1b7875751909c4a9ab9918ad322 100644
--- a/device/wake_lock/wake_lock_service_context.h
+++ b/device/wake_lock/wake_lock_service_context.h
@@ -14,7 +14,9 @@
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/sequenced_task_runner.h"
+#include "device/wake_lock/public/interfaces/wake_lock_service_context.mojom.h"
 #include "device/wake_lock/wake_lock_service_impl.h"
+#include "mojo/public/cpp/bindings/binding.h"
 #include "mojo/public/cpp/bindings/interface_request.h"
 #include "ui/gfx/native_widget_types.h"
 
@@ -22,15 +24,24 @@ namespace device {
 
 class PowerSaveBlocker;
 
-class WakeLockServiceContext {
+// Callback that maps a context ID to the NativeView associated with
+// that context.
+using WakeLockContextCallback = base::Callback<gfx::NativeView(int)>;
+
+class WakeLockServiceContext : public mojom::WakeLockServiceContext {
  public:
   WakeLockServiceContext(
+      mojom::WakeLockServiceContextRequest request,
       scoped_refptr<base::SingleThreadTaskRunner> file_task_runner,
-      base::Callback<gfx::NativeView()> native_view_getter);
-  ~WakeLockServiceContext();
+      WakeLockContextCallback native_view_getter);
+  ~WakeLockServiceContext() override;
 
-  // Creates a WakeLockServiceImpl that is strongly bound to |request|.
-  void CreateService(mojo::InterfaceRequest<mojom::WakeLockService> request);
+  // mojom::WakeLockServiceContext:
+  void SetContextID(int context_id) override;
+  void BindWakeLock(
+      mojo::InterfaceRequest<mojom::WakeLockService> request) override;
+  void HasWakeLockForTests(
+      const HasWakeLockForTestsCallback& callback) override;
 
   // Requests wake lock.
   void RequestWakeLock();
@@ -38,22 +49,29 @@ class WakeLockServiceContext {
   // Cancels pending wake lock request.
   void CancelWakeLock();
 
-  // Used by tests.
-  bool HasWakeLockForTests() const;
-
  private:
   void CreateWakeLock();
   void RemoveWakeLock();
   void UpdateWakeLock();
+  void OnConnectionError();
 
   scoped_refptr<base::SequencedTaskRunner> main_task_runner_;
   scoped_refptr<base::SingleThreadTaskRunner> file_task_runner_;
+  int context_id_;
 
   int num_lock_requests_;
 
   // The actual power save blocker for screen.
   std::unique_ptr<PowerSaveBlocker> wake_lock_;
-  base::Callback<gfx::NativeView()> native_view_getter_;
+  WakeLockContextCallback native_view_getter_;
+
+  mojo::Binding<mojom::WakeLockServiceContext> binding_;
+
+  // The number of connections that the client has in this context,
+  // including both the connection to this implementation and all
+  // connections made via |BindWakeLock()|. When this number reaches
+  // 0 this instance isn't needed anymore and kills itself.
+  int num_connections_;
 
   base::WeakPtrFactory<WakeLockServiceContext> weak_factory_;