Fix the !PlainTextRenderer so that it also works when no annotations are requested. The problem was apparent in code blocks when the highlighter(s) failed to render the block and the plain text renderer was used as a fallback.
Fix the !PlainTextRenderer so that it also works when no annotations are requested. The problem was apparent in code blocks when the highlighter(s) failed to render the block and the plain text renderer was used as a fallback.

Thanks to zimbatm on IRC for helping me to track down the issue.

Follow-up to r4399 and r4597.


git-svn-id: 0d96b0c1a6983ccc08b3732614f4d6bfcf9cbb42@4638 af82e41b-90c4-0310-8c96-b1721e28e2e2

rbaumg/trac,rbaumg/trac,rbaumg/trac,rbaumg/trac