Merged from trunk 4892:4903

Merged from trunk 4892:4903

For bug #153295, make load_infodir ignore files that contain null bytes.

For bug #153282, automatically find the owner package(s) in the event of
a fatal file collision (since the collision is fatal, the performance
hit doesn't matter).

For bug #129670, skip the replace-cvs and replace-wscomments tests if
the diff exit code indicates two two binary files that differ.

For bug #116616, only run the post_process phase if necessary.

svn path=/main/branches/prefix/; revision=4905