This CL adds a test for stepping over - among others - a reassignment of
a variable with a new named constructor.
It additionally improves the situation in DDC via kernel.
Bug:
Change-Id: I1658d433575e6614b1cbbbeb7f1765651b0d34bb
Reviewed-on: https://dart-review.googlesource.com/20667
Commit-Queue: Jens Johansen <jensj@google.com>
Reviewed-by: Johnni Winther <johnniwinther@google.com>