Only delete regular files and directories.
Only delete regular files and directories.

This ports a missing feature from PathV1.h. I am not sure how to test this
with the regular infrastructure, but an Apple bot should check this when
r183985 is reapplied.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@184119 91177308-0d34-0410-b5e6-96231b3b80d8

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