Fix Parser crashes on unknown tags/pages

Fix Parser so doesn't crash when sees an unknown tag on a known code page.
Check for unknown code page and throw parse exception.  Remove unused code.
Make class variables private where unused outside class.  Change tag stack
to ArrayDeque from fixed size static array. Check for unsupported WBXML
features: string tables, unsupported global tokens, and attributes. Throw
EasParserExceptions for all parse errors so Exchange can catch them and not
crash. Add unit tests.

Bug:14651154
Bug:14673019
Change-Id: If71be29391466985eccff90db8601bbdfde2658b
6 files changed