Compute propagated type for final instance fields (partially addresses issue 23001)

Compute propagated type for final instance fields (partially addresses issue 23001)

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

Committed: https://github.com/dart-lang/sdk/commit/8e80648c56df05f2a768655e25f1cb742b09e941

[Brian Wilkerson, 2015-10-29 17:27:45]

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

[Leaf, 2015-10-29 17:43:24]

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

[Leaf, 2015-10-29 17:43:24]

DBC: This is somewhat similar to how DDC does its inference in
InferInstanceMembersInUnitTask (possibly subsumed by it).  We've talked about
combining some of the regular mode type propagation logic and the DDC inference
logic, but I haven't really made any efforts in that direction yet - might be
some thing to keep in mind for the future.

[Paul Berry, 2015-10-29 17:49:17]

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

[Paul Berry, 2015-10-29 17:49:17]

lgtm

https://codereview.chromium.org/1410493006/diff/1/pkg/analyzer/lib/src/genera...
File pkg/analyzer/lib/src/generated/resolver.dart (right):

https://codereview.chromium.org/1410493006/diff/1/pkg/analyzer/lib/src/genera...
pkg/analyzer/lib/src/generated/resolver.dart:11568: (element.isFinal ||
element.isConst)) {
Isn't the test for `element.isConst` redundant?  I thought that all consts had
to be static, and we're already checking for `!element.isStatic`.

[scheglov, 2015-10-29 18:11:06]

LGTM

[Brian Wilkerson, 2015-10-29 18:31:04]

> This is somewhat similar to how DDC does its inference in
InferInstanceMembersInUnitTask ...

Yes, and I considered updating InstanceMemberInferrer to work for both cases,
but I thought this change had the least chance of introducing new bugs. I'll add
a comment to consider changing that in the future.

https://codereview.chromium.org/1410493006/diff/1/pkg/analyzer/lib/src/genera...
File pkg/analyzer/lib/src/generated/resolver.dart (right):

https://codereview.chromium.org/1410493006/diff/1/pkg/analyzer/lib/src/genera...
pkg/analyzer/lib/src/generated/resolver.dart:11568: (element.isFinal ||
element.isConst)) {
Actually, no. With illegal code, such as "const int f;" we will put the "const"
flag on the instance field's element. But I'm fine with removing the test; it
just means we won't have a propagated type for the invalid field.

[Brian Wilkerson, 2015-10-29 18:36:16]

Committed patchset #1 (id:1) manually as
8e80648c56df05f2a768655e25f1cb742b09e941 (presubmit successful).