0e25306d3f
Adds tests for type checks and casts using JS classes and object literals. Checks typing between different classes, same classes, object literals, subtypes, and dynamic conversions. Change-Id: I01c384395f0e6c8d671ac9bd0dc6e6905845a760 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/152990 Commit-Queue: Srujan Gaddam <srujzs@google.com> Reviewed-by: Sigmund Cherem <sigmund@google.com>