encoding: Deprecate xmlByteConsumed

This was only used by Chromium/WebKit to detect whether xmlParseContent
really succeeded. It's a horrible, overcomplicated hack.

See 8c5848bd and #767.

python/generator.py

@@ -299,6 +299,7 @@ deprecated_funcs = {
     'namePush': True,
     'nodePop': True,
     'nodePush': True,
+    'xmlByteConsumed': True,
     'xmlCheckFilename': True,
     'xmlCheckLanguageID': True,
     'xmlCleanupCharEncodingHandlers': True,