pure sdk for main

sdk/lib/webrtc/rtc_base/system/arch.h

@@ -0,0 +1,30 @@
+/*
+ *  Copyright (c) 2018 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+// This file contains platform-specific typedefs and defines.
+// Much of it is derived from Chromium's build/build_config.h.
+
+#ifndef RTC_BASE_SYSTEM_ARCH_H_
+#define RTC_BASE_SYSTEM_ARCH_H_
+
+#ifndef WEBRTC_ARCH_BIG_ENDIAN
+#define WEBRTC_ARCH_BIG_ENDIAN 
+#endif
+// Processor architecture detection.  For more info on what's defined, see:
+//   https://docs.microsoft.com/en-us/cpp/preprocessor/predefined-macros
+//   https://www.agner.org/optimize/calling_conventions.pdf
+//   https://sourceforge.net/p/predef/wiki/Architectures/
+//   or with gcc, run: "echo | gcc -E -dM -"
+
+#if !(defined(WEBRTC_ARCH_LITTLE_ENDIAN) ^ defined(WEBRTC_ARCH_BIG_ENDIAN))
+#error Define either WEBRTC_ARCH_LITTLE_ENDIAN or WEBRTC_ARCH_BIG_ENDIAN
+#endif
+
+#endif  // RTC_BASE_SYSTEM_ARCH_H_