Incremental compilation: correctly track emitted constants.

R=johnniwinther@google.com

Review URL: https://codereview.chromium.org//796463003

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@42314 260f80e4-7a28-3924-810f-c04153c831b5
First version of type propagation in the new IR.

This CL introduces typed constants and values to the IR.  As a demonstration, the types are used to eagerly statically evaluate identical(a, b) to false, if a and b have different types.

R=kmillikin@google.com

Review URL: https://codereview.chromium.org//800433003

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@42315 260f80e4-7a28-3924-810f-c04153c831b5
Customize which libraries darttags index.

R=johnniwinther@google.com

Review URL: https://codereview.chromium.org//794253002

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@42316 260f80e4-7a28-3924-810f-c04153c831b5
Incremental compilation: test giving up.

R=johnniwinther@google.com

Review URL: https://codereview.chromium.org//798533004

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@42317 260f80e4-7a28-3924-810f-c04153c831b5