Split up TypeInferrer class.

Split up TypeInferrer class.

This CL makes four classes:

- TypeInferrer, which is the API for type inference within a method
  body or field initializer, used by BodyBuilder.

- TypeInferrerImpl, which is the generic implementation of
  TypeInferrer.

- TypeInferenceEngine, which is the API for top level type inference
  and for creating TypeInferrers.

- TypeInferenceEngineImpl, which is the generic implementation of
  TypeInferenceEngine.

R=karlklose@google.com

Committed: https://github.com/dart-lang/sdk/commit/925a0a577737fd9b672c961fd080f3a7fc609fc8

[Paul Berry, 2017-04-21 11:59:50]

paulberry@google.com changed reviewers:
+ ahe@google.com, johnniwinther@google.com, karlklose@chromium.org

[karlklose, 2017-04-21 12:32:00]

karlklose@google.com changed reviewers:
+ karlklose@google.com

[karlklose, 2017-04-21 12:32:01]

LGTM, although I would prefer to use top-level and local in the names of the
inferrer classes.

[Paul Berry, 2017-04-21 12:37:36]

On 2017/04/21 12:32:01, karlklose wrote:
> LGTM, although I would prefer to use top-level and local in the names of the
> inferrer classes.

Yeah, I'm not thrilled with the current names either.  But I think that calling
them top-level and local would be misleading, because TypeInferrer is actually
used for both top-level and local inference.

The distinction is more like: TypeInferenceEngine is the object that is created
once and manages global type inference state, and TypeInferrer is the object
that is created for each method/initializer and manages state that only applies
to that method/initializer.

I'll land the CL as is for now, and if we think of better names we can always
make a follow-up change.

[Paul Berry, 2017-04-21 12:39:15]

Description was changed from

==========
Split up TypeInferrer class.

This CL makes four classes:

- TypeInferrer, which is the API for type inference within a method
  body or field initializer, used by BodyBuilder.

- TypeInferrerImpl, which is the generic implementation of
  TypeInferrer.

- TypeInferenceEngine, which is the API for top level type inference
  and for creating TypeInferrers.

- TypeInferenceEngineImpl, which is the generic implementation of
  TypeInferenceEngine.
==========

to

==========
Split up TypeInferrer class.

This CL makes four classes:

- TypeInferrer, which is the API for type inference within a method
  body or field initializer, used by BodyBuilder.

- TypeInferrerImpl, which is the generic implementation of
  TypeInferrer.

- TypeInferenceEngine, which is the API for top level type inference
  and for creating TypeInferrers.

- TypeInferenceEngineImpl, which is the generic implementation of
  TypeInferenceEngine.

R=karlklose@google.com

Committed:
https://github.com/dart-lang/sdk/commit/925a0a577737fd9b672c961fd080f3a7fc609fc8
==========

[Paul Berry, 2017-04-21 12:39:16]

Committed patchset #1 (id:1) manually as
925a0a577737fd9b672c961fd080f3a7fc609fc8 (presubmit successful).