38cec67d03
- separate new CompletionContributor and DartCompletionContributor APIs - revise new APIs and implementations to be Futures based - revise InheritedContributor to use new Futures based contributor API - remove unused classes R=brianwilkerson@google.com, scheglov@google.com Review URL: https://codereview.chromium.org/1467023002 .