63373b9e9c
This allows for supporting customized message for scanner/parser errors. Change-Id: Ib9470c3d8231de69611bc672570ae8902e9c0e6e Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/177940 Reviewed-by: Brian Wilkerson <brianwilkerson@google.com> Commit-Queue: Johnni Winther <johnniwinther@google.com>