Revert "Bug 962976 - Use a blacklist to avoid compressing specific fi…

…le types which are already compressed r=yurenju"

This reverts commit 6c99ac2.

build/webapp-zip.js

@@ -62,13 +62,7 @@ function getCompression(pathInZip, webapp) {
     webapp.metaData.zip.mmap_files.indexOf(pathInZip) !== -1) {
     return Ci.nsIZipWriter.COMPRESSION_NONE;
   } else {
-    // Don't store some files compressed since that's not giving us any
-    // benefit but costs cpu when reading from the zip.
-    var ext = pathInZip.split('.').reverse()[0].toLowerCase();
-    return (["gif", "jpg", "jpeg", "png",
-             "ogg", "opus"].indexOf(ext) !== -1)
-      ? Ci.nsIZipWriter.COMPRESSION_NONE
-      : Ci.nsIZipWriter.COMPRESSION_BEST;
+    return Ci.nsIZipWriter.COMPRESSION_BEST;
   }
 }