a17809ad18
Adds convenience method for computing the element type of a for-in iterable. Change-Id: Idd1bf0a9b80523c49130b2d7f17590dcf86d3e40 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/126581 Reviewed-by: Samir Jindel <sjindel@google.com> Commit-Queue: Johnni Winther <johnniwinther@google.com>