updated operator variant helper to have a simple version for applications that only need saved mcc and mnc values from the sim card. updated browser to use new shared helper.

added unit tests for browser bookmark, search engine customization steps.

fixed populate so that it would take a callback, changed setup so that it would wait until the right number of bookmarks are added before calling done().

fixed populate so that it would take a callback, changed setup so that it would wait until the right number of bookmarks are added before calling done().

undo styling change for DATA_URI constant.