consolidate logic to compute caption path to server-side, we don't need to do this client-side

common/lib/xmodule/xmodule/js/src/video/display/video_caption.coffee

@@ -10,10 +10,7 @@ class @VideoCaption extends Subview
       .bind('DOMMouseScroll', @onMovement)
 
   captionURL: ->
-    if @captionAssetPath != ''
-      "#{@captionAssetPath}/#{@youtubeId}.srt.sjson"
-    else
-      "/static/#{@captionDataDir}/subs/#{@youtubeId}.srt.sjson"
+    "#{@captionAssetPath}/#{@youtubeId}.srt.sjson"
 
   render: ->
     # TODO: make it so you can have a video with no captions.

common/lib/xmodule/xmodule/js/src/video/display/video_player.coffee

@@ -31,7 +31,6 @@ class @VideoPlayer extends Subview
         el: @el
         youtubeId: @video.youtubeId('1.0')
         currentSpeed: @currentSpeed()
-        captionDataDir: @video.caption_data_dir
         captionAssetPath: @video.caption_asset_path
     unless onTouchBasedDevice()
       @volumeControl = new VideoVolumeControl el: @$('.secondary-controls')

common/lib/xmodule/xmodule/video_module.py

@@ -96,9 +96,12 @@ class VideoModule(XModule):
         return self.youtube
 
     def get_html(self):
-        caption_asset_path = ''
         if isinstance(modulestore(), MongoModuleStore) :
             caption_asset_path = StaticContent.get_base_url_path_for_course_assets(self.location)
+        else:
+            # VS[compat]
+            # cdodge: filesystem static content support.
+            caption_asset_path = "/static/{0}/subs".format(self.metadata['data_dir'])
 
         return self.system.render_template('video.html', {
             'streams': self.video_list(),