[kernel] Fix loading of type argument in catch.

[kernel] Fix loading of type argument in catch.

Catch simply gave NullConstant as arguments to _instanceOf,
now I've copied what the IsExpression does, and made
LoadInstantiatorTypeArguments actually work in this case
(by filling out the scopes_->this_variable value,
by actually visiting the catch guard in the scope builder
rather than skipping it).

Fixes #29553.

BUG=
R=kmillikin@google.com

Committed: https://github.com/dart-lang/sdk/commit/202306f39be77dc84925a11cda977c950bf9e78d

[jensj, 2017-06-15 08:04:06]

jensj@google.com changed reviewers:
+ ahe@google.com, kmillikin@google.com

[ahe, 2017-06-16 13:49:46]

ahe@google.com changed reviewers:
+ vegorov@google.com

[ahe, 2017-06-16 13:49:47]

Perhaps Slava can help reviewing this.

[Kevin Millikin (Google), 2017-06-21 07:02:58]

LGTM.

https://codereview.chromium.org/2938173002/diff/1/runtime/vm/kernel_binary_fl...
File runtime/vm/kernel_binary_flowgraph.cc (right):

https://codereview.chromium.org/2938173002/diff/1/runtime/vm/kernel_binary_fl...
runtime/vm/kernel_binary_flowgraph.cc:891: VisitDartType();            // read
guard.
Update comments to be full sentences: "Read the guard."

[jensj, 2017-06-21 08:56:27]

Description was changed from

==========
[kernel] Fix loading of type argument in catch.

Catch simply gave NullConstant as arguments to _instanceOf,
now I've copied what the IsExpression does, and made
LoadInstantiatorTypeArguments actually work in this case
(by filling out the scopes_->this_variable value,
by actually visiting the catch guard in the scope builder
rather than skipping it).

Fixes #29553.

BUG=
==========

to

==========
[kernel] Fix loading of type argument in catch.

Catch simply gave NullConstant as arguments to _instanceOf,
now I've copied what the IsExpression does, and made
LoadInstantiatorTypeArguments actually work in this case
(by filling out the scopes_->this_variable value,
by actually visiting the catch guard in the scope builder
rather than skipping it).

Fixes #29553.

BUG=
R=kmillikin@google.com

Committed:
https://github.com/dart-lang/sdk/commit/202306f39be77dc84925a11cda977c950bf9e78d
==========

[jensj, 2017-06-21 08:56:28]

Committed patchset #1 (id:1) manually as
202306f39be77dc84925a11cda977c950bf9e78d (presubmit successful).