Splitting out a failing test to increase coverage of other tests.
It is not clear that `a.addAll(a)` should throw if `a` is empty.
`a` is not modified by the action.
dart2js/DDC do not detect this case and I'm reluctant to add a check
for the case where `a` is in fact not modified.
The VM test is very specific to an identical argument and cannot
detect the case for `a = Mylist([])`.
Another option to this proposal is to simply delete the `[]` case.
In general, I'd like to move more ConcurrentModificationError tests
into assert statements.
Change-Id: I1f9559bdb43ea1bae0575413748c9d9d0de58b99
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/170023
Commit-Queue: Stephen Adams <sra@google.com>
Reviewed-by: Lasse R.H. Nielsen <lrn@google.com>
Stephen Adams
e769817cdc