Add CreateWindowCapturer() and CreateScreenCapturer() in DesktopCapturer

webrtc/modules/desktop_capture/desktop_capturer.h

Index: webrtc/modules/desktop_capture/desktop_capturer.h
diff --git a/webrtc/modules/desktop_capture/desktop_capturer.h b/webrtc/modules/desktop_capture/desktop_capturer.h
index 6b9c820ce9df5ea3b739917db8e82671af0a0e86..ecae4cb2e092f2d5bb0518fe7842194407871f39 100644
--- a/webrtc/modules/desktop_capture/desktop_capturer.h
+++ b/webrtc/modules/desktop_capture/desktop_capturer.h
@@ -110,6 +110,28 @@ class DesktopCapturer {
   // Returns false in case of a failure or no source has been selected or the
   // implementation does not support this functionality.
   virtual bool FocusOnSelectedSource();
+
+  // Creates a DesktopCapturer instance which targets to capture windows.
+  static std::unique_ptr<DesktopCapturer> CreateWindowCapturer(
+      const DesktopCaptureOptions& options);
+
+  // Creates a DesktopCapturer instance which targets to capture screens.
+  static std::unique_ptr<DesktopCapturer> CreateScreenCapturer(
+      const DesktopCaptureOptions& options);
+
+ protected:
+  // CroppingWindowCapturer needs to create raw capturers without wrappers, so
+  // the following two functions are protected.
+
+  // Creates a platform specific DesktopCapturer instance which targets to
+  // capture windows.
+  static std::unique_ptr<DesktopCapturer> CreateRawWindowCapturer(
+      const DesktopCaptureOptions& options);
+
+  // Creates a platform specific DesktopCapturer instance which targets to
+  // capture screens.
+  static std::unique_ptr<DesktopCapturer> CreateRawScreenCapturer(
+      const DesktopCaptureOptions& options);
 };
 
 }  // namespace webrtc