Make AST-based type inference handle <bottom> consistently.

Make AST-based type inference handle <bottom> consistently.

The non-AST-based type inference engine has the following quirk.  With
the source code:

var x = null;

The type of `x` is inferred as `dynamic`, whereas the type of the
synthetic initializer function associated with `x` is inferred as `()
-> <bottom>`.

This CL makes the AST-based type inference engine act in the same way
for consistency.

In the future we may want to change both engines to consistently infer
`dynamic`.

R=scheglov@google.com

Committed: https://github.com/dart-lang/sdk/commit/f251da2dc9f4f8de16ebe1f85079f3f41a610a4e

[Paul Berry, 2016-05-26 22:04:04]

paulberry@google.com changed reviewers:
+ scheglov@google.com

[scheglov, 2016-05-26 22:08:13]

LGTM

[Paul Berry, 2016-05-26 22:21:34]

Description was changed from

==========
Make AST-based type inference handle <bottom> consistently.

The non-AST-based type inference engine has the following quirk.  With
the source code:

var x = null;

The type of `x` is inferred as `dynamic`, whereas the type of the
synthetic initializer function associated with `x` is inferred as `()
-> <bottom>`.

This CL makes the AST-based type inference engine act in the same way
for consistency.

In the future we may want to change both engines to consistently infer
`dynamic`.
==========

to

==========
Make AST-based type inference handle <bottom> consistently.

The non-AST-based type inference engine has the following quirk.  With
the source code:

var x = null;

The type of `x` is inferred as `dynamic`, whereas the type of the
synthetic initializer function associated with `x` is inferred as `()
-> <bottom>`.

This CL makes the AST-based type inference engine act in the same way
for consistency.

In the future we may want to change both engines to consistently infer
`dynamic`.

R=scheglov@google.com

Committed:
https://github.com/dart-lang/sdk/commit/f251da2dc9f4f8de16ebe1f85079f3f41a610a4e
==========

[Paul Berry, 2016-05-26 22:21:36]

Committed patchset #1 (id:1) manually as
f251da2dc9f4f8de16ebe1f85079f3f41a610a4e (presubmit successful).