Optimize: `return (a ? b : c)' as: `if (a) return b; else return c;'.
	* jcf-write.c (generate_bytecode_return):  New function.
	(generate_bytecode_insns):  Use it, for RETURN_EXPR.
	* jcf-write.c (generate_bytecode_insns):  For REAL_CST that is 0 or 1,
	generate special [fd]const_[01] instructions.
	* jcf-parse.c (yyparse):  Don't emit_register_classes if -fsyntax-only.
	* verify.c (verify_jvm_instructions):  Do INVALIDATE_PC after
	handling OPCODE_lookupswitch or OPCODE_tableswitch.

From-SVN: r24972