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/location.cc

@@ -0,0 +1,38 @@
+/*
+ *  Copyright 2016 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/location.h"
+
+#include "webrtc/base/stringutils.h"
+
+namespace rtc {
+
+Location::Location(const char* function_name, const char* file_and_line)
+    : function_name_(function_name), file_and_line_(file_and_line) {}
+
+Location::Location() : function_name_("Unknown"), file_and_line_("Unknown") {}
+
+Location::Location(const Location& other)
+    : function_name_(other.function_name_),
+      file_and_line_(other.file_and_line_) {}
+
+Location& Location::operator=(const Location& other) {
+  function_name_ = other.function_name_;
+  file_and_line_ = other.file_and_line_;
+  return *this;
+}
+
+std::string Location::ToString() const {
+  char buf[256];
+  sprintfn(buf, sizeof(buf), "%s@%s", function_name_, file_and_line_);
+  return buf;
+}
+
+}  // namespace rtc