Refactor analyzer-cli / ddc to share command-line / config logic

[vsmenon]

Logic around resolvers, summaries, and other context setup should be shared as much as possible. Ideally, this file in DDC and related setup calls into shared (with analyzer-cli) code instead:

https://github.com/dart-lang/sdk/blob/master/pkg/dev_compiler/lib/src/analyzer/context.dart

This will ensure analyzer-cli and ddc take consistent options and reduce work when adding new ones.

[jmesserly]

this was also filed as #27252

[danrubel]

Once https://codereview.chromium.org/2598593003/ lands, you'll be able to use all of the standard analysis options command line flags such as --options and --enable-strict-call-checks

[nex3]

@danrubel Does that mean this has been fixed?

[danrubel]

Yes. Fixed.