Get the video module pointing to the correct static files directory, without relying on get_html replacement

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

@@ -1,7 +1,7 @@
 class @Video
   constructor: (@element) ->
     @id = $(@element).attr('id').replace(/video_/, '')
-    @caption_url_base = $(@element).data('caption-url-base')
+    @caption_data_dir = $(@element).data('caption-data-dir')
     window.player = null
     @el = $("#video_#{@id}")
     @parseVideos $(@element).data('streams')

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

@@ -7,7 +7,7 @@ class @VideoCaption extends Subview
       .bind('DOMMouseScroll', @onMovement)
 
   captionURL: ->
-    "#{@captionURLBase}/#{@youtubeId}.srt.sjson"
+    "/static/#{@captionDataDir}/subs/#{@youtubeId}.srt.sjson"
 
   render: ->
     @$('.video-wrapper').after """

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

@@ -25,7 +25,11 @@ class @VideoPlayer extends Subview
 
   render: ->
     @control = new VideoControl el: @$('.video-controls')
-    @caption = new VideoCaption el: @el, youtubeId: @video.youtubeId('1.0'), currentSpeed: @currentSpeed(), captionURLBase: @video.caption_url_base
+    @caption = new VideoCaption
+        el: @el
+        youtubeId: @video.youtubeId('1.0')
+        currentSpeed: @currentSpeed()
+        captionDataDir: @video.caption_data_dir
     unless onTouchBasedDevice()
       @volumeControl = new VideoVolumeControl el: @$('.secondary-controls')
     @speedControl = new VideoSpeedControl el: @$('.secondary-controls'), speeds: @video.speeds, currentSpeed: @currentSpeed()

common/lib/xmodule/xmodule/video_module.py

@@ -71,6 +71,8 @@ class VideoModule(XModule):
             'id': self.location.html_id(),
             'position': self.position,
             'name': self.name,
+            # TODO (cpennington): This won't work when we move to data that isn't on the filesystem
+            'data_dir': self.metadata['data_dir'],
         })