Adding more detail to MessageQueue::Dispatch logging.

webrtc/base/location.cc

+/*
+ *  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