Merge r1384913, r1399687, r1419719, r1419755, r1416278, r1330189 from trunk:

Add a few AP_DEBUG_ASSERT()s for the benefit of clang


style tweak

No need to clear memory that is fully initialized just the line after.

Avoid unnecessary %s substitution

Avoid processing some files twice if APR_INCLUDEDIR and
APU_INCLUDEDIR containin the same path but differing in
doubled slashes.


Fixed position of the NEED_ENHANCED_ESCAPES define.

This define should be outside of the else case so that it
gets also defined if we cross-compile for Win32 or OS2.

Submitted by: sf, trawick, jailletc36, jailletc36, sf, fuankg
Reviewed/backported by: jim


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1439391 13f79535-47bb-0310-9956-ffa450edef68