Reland "Move webrtc/{base => rtc_base}" (https://codereview.webrtc.org/2877023002)

Reland the base->rtc_base without adding stub headers (will be
done in follow-up CL). This preserves git blame history of all files.

BUG=webrtc:7634
NOTRY=True
TBR=kwiberg@webrtc.org

Change-Id: Iea3bb6f3f67b8374c96337b63e8f5aa3e6181012
Reviewed-on: https://chromium-review.googlesource.com/554611
Reviewed-by: Henrik Kjellander <kjellander@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#18821}

webrtc/rtc_base/win32socketinit.cc

@@ -0,0 +1,46 @@
+/*
+ *  Copyright 2009 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.
+ */
+
+#include "webrtc/base/win32socketinit.h"
+
+#include "webrtc/base/win32.h"
+
+namespace rtc {
+
+// Please don't remove this function.
+void EnsureWinsockInit() {
+  // The default implementation uses a global initializer, so WSAStartup
+  // happens at module load time.  Thus we don't need to do anything here.
+  // The hook is provided so that a client that statically links with
+  // libjingle can override it, to provide its own initialization.
+}
+
+#if defined(WEBRTC_WIN)
+class WinsockInitializer {
+ public:
+  WinsockInitializer() {
+    WSADATA wsaData;
+    WORD wVersionRequested = MAKEWORD(1, 0);
+    err_ = WSAStartup(wVersionRequested, &wsaData);
+  }
+  ~WinsockInitializer() {
+    if (!err_)
+      WSACleanup();
+  }
+  int error() {
+    return err_;
+  }
+ private:
+  int err_;
+};
+WinsockInitializer g_winsockinit;
+#endif
+
+}  // namespace rtc