Add tests for these.

urlmon: The pcbRead parameter for IInternetProtocol::Read is optional, so fix the protocol implementation to check for this.

Add some missing prototypes to mscat.h.
Update win32.api to fix the winapi_check warnings.

Add some missing A/W prototype macros.
Update win32.api to fix the winapi_check warnings.

Replace LPWC?STR with LMC?STR to better match the PSDK.