948743a78c
Introduces a SourceFile based on UTF-8 byte arrays and a scanner for such source files. Substrings are computed lazily. This should save some memory because substring tokens in classes that are not used by some program are R=kasperl@google.com Review URL: https://codereview.chromium.org//27510003 git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@28843 260f80e4-7a28-3924-810f-c04153c831b5