device/bluetooth: Remove BluetoothAdapter::Start|StopDiscovering.

device/bluetooth/bluetooth_adapter.cc

Index: device/bluetooth/bluetooth_adapter.cc
diff --git a/device/bluetooth/bluetooth_adapter.cc b/device/bluetooth/bluetooth_adapter.cc
index 286815970dc7ec753539de13b45a8e3472a33369..fa66b5d5e30d4a8f6767905a3d651988456f8b47 100644
--- a/device/bluetooth/bluetooth_adapter.cc
+++ b/device/bluetooth/bluetooth_adapter.cc
@@ -29,16 +29,6 @@ void BluetoothAdapter::StartDiscoverySession(
       error_callback);
 }
 
-void BluetoothAdapter::StartDiscovering(const base::Closure& callback,
-                                        const ErrorCallback& error_callback) {
-  AddDiscoverySession(callback, error_callback);
-}
-
-void BluetoothAdapter::StopDiscovering(const base::Closure& callback,
-                                       const ErrorCallback& error_callback) {
-  RemoveDiscoverySession(callback, error_callback);
-}
-
 BluetoothAdapter::DeviceList BluetoothAdapter::GetDevices() {
   ConstDeviceList const_devices =
     const_cast<const BluetoothAdapter *>(this)->GetDevices();
@@ -124,6 +114,9 @@ void BluetoothAdapter::MarkDiscoverySessionsAsInactive() {
        iter != discovery_sessions_.end(); ++iter) {
     (*iter)->MarkAsInactive();
   }
+  // At this point, all sessions have been marked as inactive. Just remove them
+  // from our list as they are no longer relevant.
+  discovery_sessions_.clear();

[keybuk, 2014/03/06 18:42:36]

This seems to contradict the comment in the header that says that the
DiscoverySession will remove itself from the list when destroyed

[armansito, 2014/03/06 23:55:48]

Well, it doesn't really contradict it, as discovery sessions still remove
themselves. Here I clear the list as an optimization as they are really no
longer needed to be kept in the adapter's list. The comment in the header is
mostly to justify keeping raw pointers as opposed to weak pointers. I can update
the comment though, if you think that should be clarified further.

[keybuk, 2014/03/06 23:57:39]

because we're dealing with object lifetime, I think it should be clear

e.g. note that the list only contains ACTIVE discovery sessions, that they're
removed from the list when made inactive, and also removed when deleted

[armansito, 2014/03/07 19:22:16]

Actually they weren't removed when an individual one became active, but when all
of them collective got marked as inactive. I decided to change the logic so that
only pointers to active sessions are kept in |discovery_sessions_| and updated
the comments to reflect this.

 }
 
 void BluetoothAdapter::DiscoverySessionDestroyed(