Updated mediawiki/extensions
Project: mediawiki/extensions/MobileFrontend  48ac529896c8cd962fe28f11aadbc256901a113c

Regression: Banners above chrome make hamburger and echo disappear

.header needs position: relative, it's not always at the top of the
page.

Change-Id: I2f0c84570cf9cdcb0b7626239007d0af1a79f693