DesktopCaptureDevice is available when webrtc is enabled.

content/browser/renderer_host/media/video_capture_manager.cc

Index: content/browser/renderer_host/media/video_capture_manager.cc
diff --git a/content/browser/renderer_host/media/video_capture_manager.cc b/content/browser/renderer_host/media/video_capture_manager.cc
index 6af09c0411e1b71cfec71c2d414e2eb4196b9ec2..5def870612775531441268d6cd87f0ae180f7f45 100644
--- a/content/browser/renderer_host/media/video_capture_manager.cc
+++ b/content/browser/renderer_host/media/video_capture_manager.cc
@@ -40,11 +40,12 @@
 #include "media/capture/video/video_capture_device_client.h"
 #include "media/capture/video/video_capture_device_factory.h"
 
-#if defined(ENABLE_SCREEN_CAPTURE) && !defined(OS_ANDROID)
+#if BUILDFLAG(ENABLE_WEBRTC) && !defined(OS_ANDROID)

[miu, 2017/01/10 23:27:49]

Both (per prior e-mail on this CR):

  #if defined(ENABLE_SCREEN_CAPTURE) && BUILDFLAG(ENABLE_WEBRTC) &&
!defined(OS_ANDROID)

But, let's consolidate all of lines 43-53 as:

#if defined(ENABLE_SCREEN_CAPTURE)

#if BUILDFLAG(ENABLE_WEBRTC) && !defined(OS_ANDROID)
#include "content/browser/media/capture/desktop_capture_device.h"
#endif

#if defined(USE_AURA)
#include "content/browser/media/capture/desktop_capture_device_aura.h"
#endif

#if defined(OS_ANDROID)
#include "content/browser/media/capture/screen_capture_device_android.h"
#endif

#endif  // defined(ENABLE_SCREEN_CAPTURE)

[byungchul, 2017/01/10 23:48:33]

Done.

 #include "content/browser/media/capture/desktop_capture_device.h"
-#if defined(USE_AURA)
-#include "content/browser/media/capture/desktop_capture_device_aura.h"
 #endif
+
+#if defined(ENABLE_SCREEN_CAPTURE) && !defined(OS_ANDROID) && defined(USE_AURA)

[miu, 2017/01/10 23:27:50]

!defined(OS_ANDROID) is not needed (since AURA is not built on Android).

+#include "content/browser/media/capture/desktop_capture_device_aura.h"
 #endif
 
 #if defined(ENABLE_SCREEN_CAPTURE) && defined(OS_ANDROID)
@@ -683,13 +684,13 @@ VideoCaptureManager::DoStartDesktopCaptureOnDeviceThread(
   DCHECK(IsOnDeviceThread());
 
   std::unique_ptr<VideoCaptureDevice> video_capture_device;
-#if defined(ENABLE_SCREEN_CAPTURE)
   DesktopMediaID desktop_id = DesktopMediaID::Parse(id);
   if (desktop_id.is_null()) {
     device_client->OnError(FROM_HERE, "Desktop media ID is null");
     return nullptr;
   }
 
+#if defined(ENABLE_SCREEN_CAPTURE)

[miu, 2017/01/10 23:27:49]

Let's move this back up to where it was, given previous comments (and prior
e-mails).

[byungchul, 2017/01/10 23:48:33]

Done.

   if (desktop_id.type == DesktopMediaID::TYPE_WEB_CONTENTS) {
 #if defined(OS_LINUX) || defined(OS_MACOSX) || defined(OS_WIN)
     video_capture_device = WebContentsVideoCaptureDevice::Create(id);
@@ -707,12 +708,15 @@ VideoCaptureManager::DoStartDesktopCaptureOnDeviceThread(
 #if defined(USE_AURA)
     video_capture_device = DesktopCaptureDeviceAura::Create(desktop_id);
 #endif  // defined(USE_AURA)
-    if (!video_capture_device)
-      video_capture_device = DesktopCaptureDevice::Create(desktop_id);
 #endif  // defined (OS_ANDROID)
   }
 #endif  // defined(ENABLE_SCREEN_CAPTURE)
 
+#if BUILDFLAG(ENABLE_WEBRTC) && !defined(OS_ANDROID)

[miu, 2017/01/10 23:27:49]

...and move this up so that it is within the ENABLE_SCREEN_CAPTURE block.

[byungchul, 2017/01/10 23:48:33]

Done.

+  if (!video_capture_device)
+    video_capture_device = DesktopCaptureDevice::Create(desktop_id);
+#endif  // BUILDFLAG(ENABLE_WEBRTC)
+
   if (!video_capture_device) {
     device_client->OnError(FROM_HERE, "Could not create capture device");
     return nullptr;
@@ -1227,7 +1231,7 @@ void VideoCaptureManager::SetDesktopCaptureWindowIdOnDeviceThread(
     media::VideoCaptureDevice* device,
     gfx::NativeViewId window_id) {
   DCHECK(IsOnDeviceThread());
-#if defined(ENABLE_SCREEN_CAPTURE) && !defined(OS_ANDROID)
+#if BUILDFLAG(ENABLE_WEBRTC) && !defined(OS_ANDROID)
   DesktopCaptureDevice* desktop_device =
       static_cast<DesktopCaptureDevice*>(device);
   desktop_device->SetNotificationWindowId(window_id);