Add dynamic to JS foreign function calls to get implicit
downcast to T, which will cause more accurate type errors
for DDC and dart2js with -O2. Checks will be omitted
with dart2js and -O3.
Bug: #47832
Change-Id: Ie85faf47d58d748b068bc7e902a17a99292f02e4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/230823
Reviewed-by: Sigmund Cherem <sigmund@google.com>
Commit-Queue: Riley Porter <rileyporter@google.com>
