Fix escape processing in interpolated strings
Fix escape processing in interpolated strings

Change-Id: If4ed614f75a9eb1a0f42cb602fd1236cada31dd3
Reviewed-on: https://dart-review.googlesource.com/71362
Reviewed-by: Dan Rubel <5c5a7a1a3f9344592135bed55605519045cfa711@google.com>
Commit-Queue: Brian Wilkerson <1f7641b6b14c52b9163524ab8d9aabff80176f21@google.com>

dartino/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dartino/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dartino/dart-sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk,dart-lang/sdk,dart-archive/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dartino/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dartino/dart-sdk,dartino/dart-sdk