lex.c: Sync with C frontend.

lex.c: Sync with C frontend.

	* lex.c: Sync with C frontend.
	(whitespace_cr): New fn.
	(skip_white_space): Use it.
	(init_parse): Reorder.
	(yyprint): Support CONSTANT.
	(pragma_getc, pragma_ungetc): Bring back.
	(read_line_number): Change in_system_header directly.
	(handle_generic_pragma, handle_cp_pragma, yyerror): Move up in file.
	(parse_float): Update to C version.
	(yylex): Handle '$' under the letter case.
	Remove looking_for_typename handling.
	Support hex floating point constants.
	Follow C's lead for choosing type of integer constants.
	Rearrange stuff to match C frontend.
	(yyungetc, reinit_parse_for_block, yylex): Support indent_level.
	* spew.c (yylex): Clear looking_for_typename if we see a TYPESPEC.

From-SVN: r28230