Create more synthetic kernel objects.

Create more synthetic kernel objects.

This CL creates synthetic kernel objects for two additional
BodyBuilder corner cases:

- The synthetic "throw" expression created when code attempts to
  construct an abstract class.

- The "throw" expression created when code attempts to assign to a
  read-only expression.

With this change, we now create a KernelComplexAssignment object for
all assignments; this has allowed me to streamline the code for
creating assignments slightly.

R=ahe@google.com, scheglov@google.com

Committed: https://github.com/dart-lang/sdk/commit/b38e4d9a70cf2225928eb624c099aca3f2d05c3e

[Paul Berry, 2017-07-06 20:10:05]

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

[Paul Berry, 2017-07-06 20:10:05]

Konstantin to do preliminary review since he's on west coast time
Peter to do final review

[scheglov, 2017-07-06 20:14:11]

LGTM

[ahe, 2017-07-06 20:45:13]

lgtm

[Paul Berry, 2017-07-06 20:51:39]

Description was changed from

==========
Create more synthetic kernel objects.

This CL creates synthetic kernel objects for two additional
BodyBuilder corner cases:

- The synthetic "throw" expression created when code attempts to
  construct an abstract class.

- The "throw" expression created when code attempts to assign to a
  read-only expression.

With this change, we now create a KernelComplexAssignment object for
all assignments; this has allowed me to streamline the code for
creating assignments slightly.
==========

to

==========
Create more synthetic kernel objects.

This CL creates synthetic kernel objects for two additional
BodyBuilder corner cases:

- The synthetic "throw" expression created when code attempts to
  construct an abstract class.

- The "throw" expression created when code attempts to assign to a
  read-only expression.

With this change, we now create a KernelComplexAssignment object for
all assignments; this has allowed me to streamline the code for
creating assignments slightly.

R=ahe@google.com, scheglov@google.com

Committed:
https://github.com/dart-lang/sdk/commit/b38e4d9a70cf2225928eb624c099aca3f2d05c3e
==========

[Paul Berry, 2017-07-06 20:51:41]

Committed patchset #1 (id:1) manually as
b38e4d9a70cf2225928eb624c099aca3f2d05c3e (presubmit successful).