* Preserve empty lines in the file header.
* Add empty entry to the tool's newly created sections.
* Remove extra empty line at the end of the file.
Change-Id: I271583774d5f5497025a9d85bcadf8b0b9e39e81
Reviewed-on: https://dart-review.googlesource.com/37600
Commit-Queue: Alexander Thomas <athom@google.com>
Reviewed-by: William Hesse <whesse@google.com>
Alexander Thomas