[Bug 39002] New: ISAXXMLParser ignores charset property

https://bugs.winehq.org/show_bug.cgi?id=39002

Bug ID: 39002
           Summary: ISAXXMLParser ignores charset property
           Product: Wine
           Version: unspecified
          Hardware: x86
                OS: Linux
            Status: UNCONFIRMED
          Severity: minor
          Priority: P2
         Component: msxml3
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

ISAXXMLParser (or its implementation in Wine to be correct) tries to detect the
encoding of documents with xmlDetectCharEncoding and some custom heuristics in
internal_parseBuffer and uses xmlDetectCharEncoding without additional
heuristics through xmlCreatePushParserCtxt in internal_parseStream which
violates the specification:

"This setting [charset property] takes priority over the default encoding,
which is implicitly UTF-16, or over the encoding specified in the byte order
mark (BOM) of the XML document header."
(https://msdn.microsoft.com/en-us/library/ms757826%28v=vs.85%29.aspx)

Moreover, ISAXXMLParser returns E_NOTIMPL when setting the charset property. It
should at least accept ASCII, UTF-8 and UTF-16 as these encoding are detected
by internal_parseBuffer and internal_parseStream anyways and are supported by
libxml2. A better option would be to support all enconding supported by Wine
and reencode them as UTF-8 (when possible) and supply the UTF-8 encoding data
to libxml2 via custom IO callbacks.