[MR] Cancel auto-switching from tab mirroring to Cast SDK at page navigation based on user pref

chrome/browser/media/router/media_source_helper.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_helper.h"
 
 #include <stdio.h>
 
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "chrome/browser/media/router/media_source.h"
 #include "chrome/browser/sessions/session_tab_helper.h"
 #include "url/gurl.h"
 
 namespace media_router {
 
 namespace {
 
 // Prefixes used to format and detect various protocols' media source URNs.
 // See: https://www.ietf.org/rfc/rfc3406.txt
 constexpr char kTabMediaUrnFormat[] = "urn:x-org.chromium.media:source:tab:%d";
 constexpr char kDesktopMediaUrn[] = "urn:x-org.chromium.media:source:desktop";
 constexpr char kTabRemotingUrnFormat[] =
     "urn:x-org.chromium.media:source:tab_content_remoting:%d";
 constexpr char kCastPresentationUrlDomain[] = "google.com";
 constexpr char kCastPresentationUrlPath[] = "/cast";
+
+// This value must be the same as |chrome.cast.AUTO_JOIN_PRESENTATION_ID| in the
+// component extension.
+constexpr char kAutoJoinPresentationId[] = "auto-join";
+
 }  // namespace
 
 MediaSource MediaSourceForTab(int tab_id) {
   return MediaSource(base::StringPrintf(kTabMediaUrnFormat, tab_id));
 }
 
 MediaSource MediaSourceForTabContentRemoting(content::WebContents* contents) {
   DCHECK(contents);
   return MediaSource(base::StringPrintf(kTabRemotingUrnFormat,
                                         SessionTabHelper::IdForTab(contents)));
@@ skipping 17 matching lines @@
   return sscanf(source.id().c_str(), kTabMediaUrnFormat, &tab_id) == 1 &&
       tab_id > 0;
 }
 
 bool IsMirroringMediaSource(const MediaSource& source) {
   return IsDesktopMirroringMediaSource(source) ||
          IsTabMirroringMediaSource(source);
 }
 
 bool CanConnectToMediaSource(const MediaSource& source) {
   // compare host, port, scheme, and path prefix for source.url()

[apacible, 2016/12/09 18:04:09]

nit: capitalize "compare" and period at the end of comment.

[takumif, 2016/12/09 19:18:12]

Done.

   if (!source.url().SchemeIs(url::kHttpsScheme) ||

[apacible, 2016/12/09 18:04:09]

Personal preference to just have this function just have a return statement
(rather than if() return x, return y), but up to you.

[takumif, 2016/12/09 19:18:12]

Changed.

       !source.url().DomainIs(kCastPresentationUrlDomain) ||
       (!source.url().has_path() ||
        source.url().path() != kCastPresentationUrlPath))
     return false;
 
   return true;
 }
 
 int TabIdFromMediaSource(const MediaSource& source) {
   int tab_id;
   if (sscanf(source.id().c_str(), kTabMediaUrnFormat, &tab_id) == 1)
     return tab_id;
   else if (sscanf(source.id().c_str(), kTabRemotingUrnFormat, &tab_id) == 1)
     return tab_id;
   else
     return -1;
 }
 
 bool IsValidMediaSource(const MediaSource& source) {
   return TabIdFromMediaSource(source) > 0 ||
          IsDesktopMirroringMediaSource(source) ||
          IsValidPresentationUrl(GURL(source.id()));
 }
 
 bool IsValidPresentationUrl(const GURL& url) {
   return url.is_valid() && url.SchemeIsHTTPOrHTTPS();
 }
 
+bool IsAutoJoinPresentationId(const std::string& presentation_id) {
+  return presentation_id == kAutoJoinPresentationId;
+}
+
 }  // namespace media_router