Generate all extension schema namespaces as "api" and instead vary the generated bundle names.

extensions/browser/api/bluetooth/bluetooth_api_utils.h

 // Copyright (c) 2012 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.
 
 #ifndef EXTENSIONS_BROWSER_API_BLUETOOTH_BLUETOOTH_API_UTILS_H_
 #define EXTENSIONS_BROWSER_API_BLUETOOTH_BLUETOOTH_API_UTILS_H_
 
 #include "base/values.h"
 #include "device/bluetooth/bluetooth_adapter.h"
 #include "device/bluetooth/bluetooth_device.h"
 #include "extensions/common/api/bluetooth.h"
 
 namespace extensions {
-namespace core_api {
+namespace api {
 namespace bluetooth {
 
 // Fill in a Device object from a BluetoothDevice.
 void BluetoothDeviceToApiDevice(
     const device::BluetoothDevice& device,
     Device* out);
 
 // Fill in an AdapterState object from a BluetoothAdapter.
 void PopulateAdapterState(const device::BluetoothAdapter& adapter,
                           AdapterState* out);
 
 }  // namespace bluetooth
-}  // namespace core_api
+}  // namespace api
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_API_BLUETOOTH_BLUETOOTH_API_UTILS_H_