Lazy-creates BluetoothAdapter in ExtensionBluetoothEventRouter (EBEE).

chrome/browser/extensions/bluetooth_event_router.h

Index: chrome/browser/extensions/bluetooth_event_router.h
diff --git a/chrome/browser/extensions/bluetooth_event_router.h b/chrome/browser/extensions/bluetooth_event_router.h
index 657053879190b2520ae6f936a4d4e8c665fa1105..f521a170721673d2798d434fcd90fee00e459629 100644
--- a/chrome/browser/extensions/bluetooth_event_router.h
+++ b/chrome/browser/extensions/bluetooth_event_router.h
@@ -6,6 +6,7 @@
 #define CHROME_BROWSER_EXTENSIONS_BLUETOOTH_EVENT_ROUTER_H_
 
 #include <map>
+#include <string>
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_vector.h"
@@ -24,15 +25,17 @@ class ExtensionBluetoothEventRouter
 
   // adapter() will return NULL if the bluetooth adapter is not supported in the
   // current platform.
-  const device::BluetoothAdapter* adapter() const {
-    return adapter_.get();
-  }
+  scoped_refptr<const device::BluetoothAdapter> adapter();
 
   // GetMutableAdapter will return NULL if the bluetooth adapter is not
   // supported in the current platform.
-  device::BluetoothAdapter* GetMutableAdapter() {
-    return adapter_.get();
-  }
+  scoped_refptr<device::BluetoothAdapter> GetMutableAdapter();
+
+  // Called when an event listener is added.
+  void OnEventListenerAdded(const std::string& event_name);
+
+  // Called when an event listener is removed.
+  void OnEventListenerRemoved(const std::string& event_name);
 
   // Register the BluetoothSocket |socket| for use by the extensions system.
   // This class will hold onto the socket for its lifetime, or until
@@ -73,7 +76,15 @@ class ExtensionBluetoothEventRouter
   void SetAdapterForTest(device::BluetoothAdapter* adapter) {
     adapter_ = adapter;
   }
+
  private:
+  static bool IsBluetoothEvent(const std::string& event_name);
+
+  bool IsAdapterNeeded() const;
+
+  void InitializeAdapterIfNeeded();
+  void MaybeReleaseAdapter();
+
   void DispatchBooleanValueEvent(const char* event_name, bool value);
 
   bool send_discovery_events_;
@@ -82,6 +93,8 @@ class ExtensionBluetoothEventRouter
   Profile* profile_;
   scoped_refptr<device::BluetoothAdapter> adapter_;
 
+  int num_event_listeners_;
+
   // The next id to use for referring to a BluetoothSocket.  We avoid using
   // the fd of the socket because we don't want to leak that information to
   // the extension javascript.