bluetooth: Invalidate connection objects if a connection fails and add histograms

device/bluetooth/bluetooth_device.cc

Index: device/bluetooth/bluetooth_device.cc
diff --git a/device/bluetooth/bluetooth_device.cc b/device/bluetooth/bluetooth_device.cc
index e666aa5c870785788f24031163407101a6ef8146..79e2caf2386f90cf94cd0ed8d6df649eb6bf532a 100644
--- a/device/bluetooth/bluetooth_device.cc
+++ b/device/bluetooth/bluetooth_device.cc
@@ -297,17 +297,21 @@ void BluetoothDevice::DidFailToConnectGatt(ConnectErrorCode error) {
     error_callback.Run(error);
   create_gatt_connection_success_callbacks_.clear();
   create_gatt_connection_error_callbacks_.clear();
+
+  // TODO(ortuno): We shouldn't need to invalidate connections since
+  // DidFailToConnectGatt should only be called when a connection attempt
+  // fails and there are no connection objects.
+  // http://crbug.com/570850
+  for (BluetoothGattConnection* connection : gatt_connections_) {

[scheib, 2016/01/15 01:39:45]

DCHECK this instead.

[ortuno, 2016/01/15 21:34:41]

Done.

+    connection->InvalidateConnectionReference();
+  }
+  gatt_connections_.clear();
 }
 
 void BluetoothDevice::DidDisconnectGatt() {
   // Pending calls to connect GATT are not expected, if they were then
-  // DidFailToConnectGatt should be called. But in case callbacks exist
-  // flush them to ensure a consistent state.
-  if (create_gatt_connection_error_callbacks_.size() > 0) {
-    VLOG(1) << "Unexpected / unexplained DidDisconnectGatt call while "
-               "create_gatt_connection_error_callbacks_ are pending.";
-  }
-  DidFailToConnectGatt(ERROR_FAILED);
+  // DidFailToConnectGatt should have been called.
+  CHECK(!create_gatt_connection_error_callbacks_.size());

[scheib, 2016/01/15 01:39:44]

If you use CHECK, please TODO and file a ship blocking issue to return to
DCHECK.

I think DCHECK is sufficient though.

[ortuno, 2016/01/15 21:34:41]

Done.

 
   // Invalidate all BluetoothGattConnection objects.
   for (BluetoothGattConnection* connection : gatt_connections_) {