bluetooth: Make device/bluetooth a shared library component.

device/bluetooth/bluetooth_init_win.h

Index: device/bluetooth/bluetooth_init_win.h
diff --git a/device/bluetooth/bluetooth_init_win.h b/device/bluetooth/bluetooth_init_win.h
index 57fe5d79484715c3d9ad2cecbcd6f504fe1ea67c..ac8f7f0d13cb74fe048f9cca12f78088b9cb007f 100644
--- a/device/bluetooth/bluetooth_init_win.h
+++ b/device/bluetooth/bluetooth_init_win.h
@@ -17,6 +17,8 @@
 #include <ws2def.h>
 #include <ws2bth.h>
 
+#include "device/bluetooth/bluetooth_export.h"
+
 #pragma comment(lib, "Bthprops.lib")
 #pragma comment(lib, "BluetoothApis.lib")
 
@@ -26,7 +28,7 @@ namespace bluetooth_init_win {
 // Returns true if the machine has a bluetooth stack available. The first call
 // to this function will involve file IO, so it should be done on an appropriate
 // thread. This function is not thread-safe.
-bool HasBluetoothStack();
+bool DEVICE_BLUETOOTH_EXPORT HasBluetoothStack();
 
 }  // namespace bluetooth_init_win
 }  // namespace device