Desktop chrome tab capture-chooseDesktopMedia()

content/public/browser/web_contents_media_capture_id.h

Index: content/public/browser/web_contents_media_capture_id.h
diff --git a/content/public/browser/web_contents_media_capture_id.h b/content/public/browser/web_contents_media_capture_id.h
new file mode 100644
index 0000000000000000000000000000000000000000..f96e09a5bd4d4b93923b0fceef9ecbbc40b76b30
--- /dev/null
+++ b/content/public/browser/web_contents_media_capture_id.h
@@ -0,0 +1,66 @@
+// Copyright (c) 2015 The Chromium Authors. All rights reserved.

[mark a. foltz, 2016/01/04 20:11:41]

s/2015/2016/

[GeorgeZ, 2016/01/06 22:41:39]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_MEDIA_CAPTURE_ID_H_
+#define CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_MEDIA_CAPTURE_ID_H_
+
+#include <string>
+
+#include "content/common/content_export.h"
+
+namespace content {
+const char kWebContentsCaptureScheme[] = "web-contents-media-stream";
+
+struct CONTENT_EXPORT WebContentsMediaCaptureId {

[mark a. foltz, 2016/01/04 20:11:41]

Where is the syntax of this ID defined?  Can you include documentation or a
link?

[miu, 2016/01/05 01:43:09]

mfoltz: There is none.  Note that gyzhou@ has simply moved
content/browser/media/capture/web_contents_util.* into this file/class at my
earlier request because he needs to use it for this new feature as well.  Before
this change, there were only two code points using this
(chrome/browser/extensions/api/tab_capture/tab_capture_api.cc and
content/browser/media/capture/web_contents_util.cc).

Eventually, we should do some housekeeping in the tab capture API code to
eliminate the need for this ID
(https://code.google.com/p/chromium/issues/detail?id=163100#c19, see comment
19).

+ public:
+  // Represents an "unset" value for either |render_process_id| or
+  // |main_render_frame_id|.
+  static const int kInvalidId = -1;
+
+  WebContentsMediaCaptureId() = default;
+  WebContentsMediaCaptureId(int render_process_id, int main_render_frame_id)
+      : render_process_id(render_process_id),
+        main_render_frame_id(main_render_frame_id) {}
+
+  WebContentsMediaCaptureId(int render_process_id,
+                            int main_render_frame_id,
+                            bool enable_auto_throttling)
+      : render_process_id(render_process_id),
+        main_render_frame_id(main_render_frame_id),
+        enable_auto_throttling(enable_auto_throttling) {}
+
+  bool operator<(const WebContentsMediaCaptureId& other) const;
+  bool operator==(const WebContentsMediaCaptureId& other) const;
+
+  // Return true if render_process_id or main_render_frame_id is invalid.
+  bool is_null() const;
+
+  std::string ToString() const;
+
+  // Tab video and audio capture need render process id and render frame id.
+  int render_process_id = kInvalidId;
+  int main_render_frame_id = kInvalidId;
+
+  bool enable_auto_throttling = false;

[Sergey Ulanov, 2016/01/04 18:59:29]

Why is this part of the window identifier?

[GeorgeZ, 2016/01/06 22:41:39]

This file was moved from
content/browser/media/capture/web_contents_capture_util.* as a comment of a
reviewer and author of the file. He asked me to keep this parameter otherwise
some of his code will break.

+
+  // Create WebContentsMediaCaptureId based on a string.
+  static WebContentsMediaCaptureId Parse(const std::string& str);
+
+  // Check whether the device id indicates that this is a web contents stream.
+  static bool IsWebContentsDeviceId(const std::string& device_id);

[mark a. foltz, 2016/01/04 20:11:41]

Why static?

[GeorgeZ, 2016/01/06 22:41:39]

This file was moved from
content/browser/media/capture/web_contents_capture_util.* as a comment of a
reviewer and author of the file. This function is used by his code as a static
function.

+
+  // Function to extract the target render frame id's from a media stream
+  // request's device id.
+  static bool ExtractTabCaptureTarget(const std::string& device_id,

[mark a. foltz, 2016/01/04 20:11:41]

Ditto

[GeorgeZ, 2016/01/06 22:41:39]

same as previous.

+                                      int* render_process_id,
+                                      int* main_render_frame_id);
+
+  // Parses the media stream request |device_id| and returns true if both 1) the
+  // format is valid, and 2) the throttling option is set to auto.
+  static bool IsAutoThrottlingOptionSet(const std::string& device_id);

[mark a. foltz, 2016/01/04 20:11:41]

Ditto

[GeorgeZ, 2016/01/06 22:41:39]

Same as previous.

+};
+
+}  // namespace content
+
+#endif  // CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_MEDIA_CAPTURE_ID_H_