Make definition of _vorbis_window_get() match declaration.

window.c wasn't actually including window.h, or this would have been
 noticed earlier.


git-svn-id: http://svn.xiph.org/trunk/vorbis@19028 0101bb08-14d6-0310-b084-bc0e0c8e3800
Various warning fixes.

Some of these were introduced in r19028.
Others have been around much longer.


git-svn-id: http://svn.xiph.org/trunk/vorbis@19031 0101bb08-14d6-0310-b084-bc0e0c8e3800
Merge remote-tracking branch 'upstream/master'