Fix infinite recursion in canonicalize

It's possible for a class A to be both a sub-class and the enclosing
instance of another class B:

```
class Test {
  class B {}
  class A extends B {
    A.B f;
  }
}
```

During canonicalization we don't need to consider both possibilities
simultaneously. When canonicalizing B as a member of A we end up
canonicalizing A's super-type, but the enclosing instance for the second
step should be A's outer class, not A itself. This was causing
canonicalization to get stuck in an infinite loop on examples like the
one above.

MOE_MIGRATED_REVID=179932866

1 files changed, 2 insertions, 1 deletions

diff --git a/java/com/google/turbine/types/Canonicalize.java b/java/com/google/turbine/types/Canonicalize.java
index b4e320d..fc5d907 100644
--- a/java/com/google/turbine/types/Canonicalize.java
+++ b/java/com/google/turbine/types/Canonicalize.java
@@ -195,7 +195,8 @@ public class Canonicalize {
         }
         break;
       }
-      curr = canon(env, curr.sym(), env.get(curr.sym()).superClassType());
+      TypeBoundClass info = env.get(curr.sym());
+      curr = canon(env, info.owner(), info.superClassType());
     }
     simples.add(ty);
     return new ClassTy(simples.build());