Introduce the ENABLE_BROWSER_CDMS macro.

content/content_browser.gypi

Index: content/content_browser.gypi
diff --git a/content/content_browser.gypi b/content/content_browser.gypi
index 8fcf1b12dae59a96dfa535e7429388261e1d5317..f219725f3fbeef86be9c6622b71ec92b11871c0f 100644
--- a/content/content_browser.gypi
+++ b/content/content_browser.gypi
@@ -790,8 +790,6 @@
       'browser/media/android/media_drm_credential_manager.h',
       'browser/media/android/media_resource_getter_impl.cc',
       'browser/media/android/media_resource_getter_impl.h',
-      'browser/media/android/media_web_contents_observer.cc',
-      'browser/media/android/media_web_contents_observer.h',
       'browser/media/capture/audio_mirroring_manager.cc',
       'browser/media/capture/audio_mirroring_manager.h',
       'browser/media/capture/content_video_capture_device_core.cc',
@@ -806,8 +804,6 @@
       'browser/media/capture/web_contents_tracker.h',
       'browser/media/capture/web_contents_video_capture_device.cc',
       'browser/media/capture/web_contents_video_capture_device.h',
-      'browser/media/cdm/browser_cdm_manager.cc',
-      'browser/media/cdm/browser_cdm_manager.h',
       'browser/media/media_internals.cc',
       'browser/media/media_internals.h',
       'browser/media/media_internals_handler.cc',
@@ -1763,5 +1759,13 @@
         'browser/geolocation/wifi_data_provider_linux.cc',
       ],
     }],
+    ['enable_browser_cdms==1', {
+      'sources': [
+        'browser/media/cdm/browser_cdm_manager.cc',
+        'browser/media/cdm/browser_cdm_manager.h',
+        'browser/media/media_web_contents_observer.cc',
+        'browser/media/media_web_contents_observer.h',

[xhwang, 2014/06/05 00:21:25]

This is working for Android because Android always
definesenable_browser_cdms==1.

+      ],
+    }],
   ],
 }