Added the audio picker to the single selection.

WordPress/src/main/java/org/wordpress/android/ui/media/MediaBrowserActivity.java

@@ -713,7 +713,8 @@ public void onMediaItemSelected(int localMediaId, boolean isLongClick) {
                 || mBrowserType.isPicker() && isLongClick) {
             showMediaSettings(media);
         } else if ((mBrowserType.isSingleImagePicker() || mBrowserType.isSingleMediaPicker() || mBrowserType
-                .isSingleFilePicker()) && !isLongClick) {
+                .isSingleFilePicker()) || mBrowserType
+                .isSingleAudioFilePicker() && !isLongClick) {
             // if we're picking a single image, we're done
             Intent intent = new Intent();
             ArrayList<Long> remoteMediaIds = new ArrayList<>();