Add media router common classes and unittests.

chrome/browser/media/router/media_source.cc

+// Copyright 2015 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.
+
+#include "chrome/browser/media/router/media_source.h"
+
+#include "base/strings/string_util.h"
+#include "base/strings/stringprintf.h"
+#include "url/gurl.h"
+
+namespace media_router {
+
+namespace {
+
+// See: https://www.ietf.org/rfc/rfc3406.txt
+const char kTabMediaUrnPrefix[] = "urn:x-org.chromium.media:source:tab";
+const char kDesktopMediaUrn[] = "urn:x-org.chromium.media:source:desktop";
+const char kCastUrnPrefix[] = "urn:x-com.google.cast:application:";
+
+bool IdSupportsMirroring(const std::string& id) {
+  return StartsWithASCII(id, kDesktopMediaUrn, true) ||
+         StartsWithASCII(id, kTabMediaUrnPrefix, true);
+}
+
+}  // namespace
+
+MediaSource::MediaSource(const std::string& source_id) : id_(source_id) {}
+
+MediaSource::~MediaSource() {}
+
+
+const std::string& MediaSource::id() const {
+  return id_;
+}
+
+// static
+MediaSource MediaSource::ForTab(int tab_id) {
+  return MediaSource(base::StringPrintf("%s:%d", kTabMediaUrnPrefix, tab_id));
+}
+
+// static
+MediaSource MediaSource::ForDesktop() {
+  return MediaSource(std::string(kDesktopMediaUrn));
+}
+
+// static
+// TODO(mfoltz): Remove when the TODO in
+// MediaSourceManager::GetDefaultMediaSource is resolved.
+MediaSource MediaSource::ForCastApp(const std::string& app_id) {
+  return MediaSource(kCastUrnPrefix + app_id);
+}
+
+// static
+MediaSource MediaSource::ForPresentationUrl(
+    const std::string& presentation_url) {
+  return MediaSource(presentation_url);
+}
+
+bool MediaSource::Parse(const std::string& id) {
+  if (!IdSupportsMirroring(id) &&
+      !StartsWithASCII(id, kCastUrnPrefix, true)) {
+    GURL url(id);
+    if (!url.is_valid() || !url.SchemeIsHTTPOrHTTPS()) {
+      return false;
+    }
+  }
+  id_ = id;
+  return true;
+}
+
+bool MediaSource::SupportsMirroring() const {
+  return IdSupportsMirroring(id_);
+}
+
+}  // namespace media_router