Revert "[Desktop Capturer] Use new DesktopAndCursorComposer constructor"

This reverts commit cf3aebae.

Reason for revert: The new API breaks on X11 and Mac OSX.

Original change's description:
> [Desktop Capturer] Use new DesktopAndCursorComposer constructor
> 
> After several changes, we finally removed the dependency of SourceId in
> MouseCursorMonitor. Now DesktopAndCursorComposer provides a clearer
> constructor for its clients.
> 
> Bug: webrtc:7950
> Change-Id: I8716d736897637412e712fcc2b2d17ef0acf3eab
> Reviewed-on: https://chromium-review.googlesource.com/651147
> Commit-Queue: Zijie He <zijiehe@chromium.org>
> Reviewed-by: Jamie Walch <jamiewalch@chromium.org>
> Reviewed-by: Weiyong Yao <braveyao@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#500761}

TBR=jamiewalch@chromium.org,braveyao@chromium.org,zijiehe@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: webrtc:7950, chromium:778035, chromium:778049
Change-Id: I45fbc68ae52194164828bc34207fe849850a98bf
Reviewed-on: https://chromium-review.googlesource.com/746947Reviewed-by: Weiyong Yao <braveyao@chromium.org>
Reviewed-by: Zijie He <zijiehe@chromium.org>
Commit-Queue: Zijie He <zijiehe@chromium.org>
Cr-Commit-Position: refs/heads/master@{#512976}

content/browser/media/capture/desktop_capture_device.cc

@@ -434,7 +434,8 @@ std::unique_ptr<media::VideoCaptureDevice> DesktopCaptureDevice::Create(
           webrtc::DesktopCapturer::CreateScreenCapturer(options));
       if (screen_capturer && screen_capturer->SelectSource(source.id)) {
         capturer.reset(new webrtc::DesktopAndCursorComposer(
-            std::move(screen_capturer), options));
+            screen_capturer.release(),
+            webrtc::MouseCursorMonitor::CreateForScreen(options, source.id)));
         IncrementDesktopCaptureCounter(SCREEN_CAPTURER_CREATED);
         IncrementDesktopCaptureCounter(
             source.audio_share ? SCREEN_CAPTURER_CREATED_WITH_AUDIO
@@ -449,7 +450,8 @@ std::unique_ptr<media::VideoCaptureDevice> DesktopCaptureDevice::Create(
       if (window_capturer && window_capturer->SelectSource(source.id)) {
         window_capturer->FocusOnSelectedSource();
         capturer.reset(new webrtc::DesktopAndCursorComposer(
-            std::move(window_capturer), options));
+            window_capturer.release(),
+            webrtc::MouseCursorMonitor::CreateForWindow(options, source.id)));
         IncrementDesktopCaptureCounter(WINDOW_CAPTURER_CREATED);
       }
       break;