file resources: MDL-14541 Object tag embedding PDF's and nested Flash objects does not work reliably
file resources: MDL-14541 Object tag embedding PDF's and nested Flash objects does not work reliably

Merged from MOODLE_19_STABLE.

Credit goes to David Boyer for reporting and suggesting the fix for PDF files,
and Jon Witts & Mauno Korpelainen for proving a way to reproduce the Flash
issue and tips to fix it.

dilawar/moodle