Avoid an assert fault in snapshot writer by making sure that the parent of a

Avoid an assert fault in snapshot writer by making sure that the parent of a
signature function is also a signature function (fixes #29994).

R=rmacnak@google.com

Committed: https://github.com/dart-lang/sdk/commit/bb527cb89e554388ae986fa754705c5b7710a561

[regis, 2017-06-23 18:37:13]

regis@google.com changed reviewers:
+ rmacnak@google.com

[rmacnak, 2017-06-23 20:25:59]

On 2017/06/23 18:37:14, regis wrote:

Does this allow CheckFunctionTypesVisitor to stop skipping signature functions?

[regis, 2017-06-23 20:36:05]

On 2017/06/23 20:25:59, rmacnak wrote:
> On 2017/06/23 18:37:14, regis wrote:
> 
> Does this allow CheckFunctionTypesVisitor to stop skipping signature
functions?

No, it is unrelated. Skipping signature functions in CheckFunctionTypesVisitor
is required as explained by this comment:
      // Signature functions get created, but not canonicalized, when function
      // types get instantiated during run time type tests.

This cl only guarantees that a function type does not point to any regular
function (even via the parent function chain), but only to signature functions.
The snapshot writer got confused when a regular function was reached, but did
not have any code.

[rmacnak, 2017-06-23 21:13:50]

LGTM

[regis, 2017-06-23 21:18:19]

Description was changed from

==========
Avoid an assert fault in snapshot writer by making sure that the parent of a
signature function is also a signature function (fixes #29994).
==========

to

==========
Avoid an assert fault in snapshot writer by making sure that the parent of a
signature function is also a signature function (fixes #29994).

R=rmacnak@google.com

Committed:
https://github.com/dart-lang/sdk/commit/bb527cb89e554388ae986fa754705c5b7710a561
==========

[regis, 2017-06-23 21:18:20]

Committed patchset #1 (id:1) manually as
bb527cb89e554388ae986fa754705c5b7710a561 (presubmit successful).