* coretypes.h (cpp_reader): Forward declare struct.
        * c-pragma.h (cpp_reader): Remove forward declaration.
        * hashtable.h (cpp_reader): Likewise.
        * scan.h (cpp_reader): Likewise.
        * tree.h (cpp_reader): Likewise.
        * config/darwin-protos.h (cpp_reader): Likewise.
        * config/arm/arm-protos.h (cpp_reader): Likewise.
        * config/rs6000/rs6000-protos.h: Remove GCC_CPPLIB_H ifdef, use
        struct cpp_reader in prototypes.

From-SVN: r62050