Removal of separate preprocessor cpp0.

	* Makefile.in (GCC_PASSES, STAGESTUFF, LIBCPP_OBJS,
	cpp0, install-common): Update.
	* c-common.c (flag_preprocess_only): New.
	(c_common_init): Preprocess for -E.
	* c-common.h (flag_preprocess_only): New.
	* c-decl.c (c_decode_option): Handle -E, and -std=c++98.
	* c-objc-common.c (c_init_decl_processing): Exit quickly
	for NULL return from c_common_init.
	* cpplib.h (cpp_preprocess_file): New.
	* cppmain.c (main, general_init, pfile, progname): Remove.
	(do_preprocessing): Rename cpp_preprocess_file, don't call
	cpp_finish.  Don't close stdout here.
	(setup_callbacks): Update prototype.
	* gcc.c (trad_capable_cpp, cpp_unique_options, default_compilers):
	Update.
	* tradcpp.c (main): Ignore -quiet.
cp:
	* decl2.c (cxx_decode_option): Handle -E.
	* lang-specs.h (default_compilers): Preprocess with cc1plus.
	* lex.c (cxx_init): Exit quickly if c_common_init returns NULL.
objc:
	* lang-specs.h (default_compilers): Preprocess with cc1obj.

Co-Authored-By: Aldy Hernandez <aldyh@redhat.com>

From-SVN: r51256