The object type key does not need to be provided
first. Previously, content was skipped until the
"ty" type key was found. If the key was placed at
the end, the entire object was ignored.
Now, before parsing subsequent elements, finding
the "ty" key is enforced. Since in-situ parsing
does not support backtracking, the key is searched
with an internal function.
Introducing support for the "ty" key placed anywhere
highlighted the use of redundant logic for parsing
the list of shapes — this duplicate logic has been
removed.
