Move chrome.bluetoothLowEnergy out of //chrome.

extensions/browser/api/bluetooth_low_energy/BUILD.gn

+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+source_set("bluetooth_low_energy") {
+  sources = [
+    "bluetooth_api_advertisement.cc",
+    "bluetooth_api_advertisement.h",
+    "bluetooth_low_energy_api.cc",
+    "bluetooth_low_energy_api.h",
+    "bluetooth_low_energy_connection.cc",
+    "bluetooth_low_energy_connection.h",
+    "bluetooth_low_energy_event_router.cc",
+    "bluetooth_low_energy_event_router.h",
+    "bluetooth_low_energy_notify_session.cc",
+    "bluetooth_low_energy_notify_session.h",
+    "utils.cc",
+    "utils.h",
+  ]
+
+  configs += [
+    # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
+    "//build/config/compiler:no_size_t_to_int_warning",
+  ]
+
+  deps = [
+    "//device/bluetooth",
+  ]
+}