Bug 1713 - You can't check the existence of a typedef using the preprocessor. Added a preprocessor check. Also removed an overqualified method name.
## a message with an invalid boolean value
## VALID_HEADER includes a LENGTH Header and LENGTH Body
VALID_HEADER method_call
HEADER_FIELD INTERFACE
TYPE STRING
STRING 'org.freedesktop.Foo'
HEADER_FIELD MEMBER
TYPE STRING
STRING 'Bar'
HEADER_FIELD PATH
TYPE OBJECT_PATH
OBJECT_PATH '/foo'
ALIGN 8
END_LENGTH Header
START_LENGTH Body
TYPE BOOLEAN
BYTE 3
END_LENGTH Body