Don't explicitly walk summary function.

Change-Id: Ibb540f715e1a4560b60c6f7f8aadb7f676b2e6bb
Preserve access functions in optimizer.

Change-Id: I349617c66a778b29c6497a2cb178dbac68c3d158
Allow implicit conversion from int to bool.

Change-Id: I83c68008c55a02dfaad2e42cbc374035c1fbcd9c
Preserve function prototypes for non-header functions.

Function prototypes, not declared in header files (supplied by
--include options) are preserved.

Change-Id: Ic5972c11fce834c1f248caaecf482fa35a8ec97f