- Fix the XL layout: Don't refer to "GONE" views in RelativeLayout.
- Don't always (re-)load message on onResume().
This will make it lose all state (e.g. webview's zoom level) when coming
back from other activities.
- Change the default visibility of some views so that it'll look okay
while loading the message.
- Remove the use of obsolete fragment APIs.
- And some other minor cleanups...
Bug 3221066
Change-Id: I475bc229f4ea9e0e480f528389f5180e1d63fcd6
