Bug 1536766 - Re-label two files in gPlayTests as video, since they contain video tracks. r=jya

Differential Revision: https://phabricator.services.mozilla.com/D27258

--HG--
extra : moz-landing-system : lando

dom/media/test/manifest.js

@@ -233,8 +233,8 @@ var gPlayTests = [
   { name:"bug495794.ogg", type:"audio/ogg", duration:0.3 },
   { name:"bug557094.ogv", type:"video/ogg", duration:0.24 },
   { name:"multiple-bos.ogg", type:"video/ogg", duration:0.431 },
-  { name:"audio-overhang.ogg", type:"audio/ogg", duration:2.3 },
-  { name:"video-overhang.ogg", type:"audio/ogg", duration:3.966 },
+  { name:"audio-overhang.ogg", type:"video/ogg", duration:2.3 },
+  { name:"video-overhang.ogg", type:"video/ogg", duration:3.966 },
 
   // bug461281.ogg with the middle second chopped out.
   { name:"audio-gaps.ogg", type:"audio/ogg", duration:2.208 },