gn-build: Add bluetooth-service target

This patch makes the Bluetooth system service (service/) buildable using GN:

1. Added new BUILD.gn file for service/
2. Added conditional compilation for global config paths, with TODOs for
generalizing them later.
3. Added a shim for loading the Bluetooth library that calls hw_get_module on
Android and explicitly calls dlopen on OS_GENERIC.
4. Fixed compile warnings and errors.
5. Did some minor clean up in gatt_server.cpp for better readability.

Bug: 22124644
Change-Id: I3226537a3a5211a6762651a35707638df29956b0

1 files changed, 3 insertions, 0 deletions

diff --git a/BUILD.gn b/BUILD.gn
index 10cefaac38..c9c55eb5f3 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1,4 +1,5 @@
 #
+#
 #  Copyright (C) 2015 Google, Inc.
 #
 #  Licensed under the Apache License, Version 2.0 (the "License");
@@ -24,5 +25,7 @@
 group("bluetooth") {
   deps = [
     "//main:bluetooth.default",
+    "//service:bluetoothtbd",
+    "//vendor_libs:vendor-libs"
   ]
 }