Fix bug in range analysis.
Fix bug in range analysis.

A definition that is in the same block as a phi can never
dominate the phi, since phis are at the very start of a block.

R=vegorov@google.com

Review URL: https://codereview.chromium.org//556353002

git-svn-id: c93d8a2297af3b929165606efe145742a534bc71@40102 260f80e4-7a28-3924-810f-c04153c831b5

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