This CL is to resolve a TODO. I couldn't find a way to trigger any bugs
in the code, but I did add a test. I believe that the reason I couldn't
trigger a bug is because any constructor that has a null `typeName`
will not have a simple identifier in a place that would allow
`_isConstructorDeclarationReturnType` to be invoked.
I realized, while looking at the code, that the type check is
unnecessary. If the type name is null, then the test will somply return
`false`, which is what we'd expect it to do. Given that it isn't needed,
I decided to remove it.
Change-Id: Ib36aaf16475db0db5817e65a8b8bfbb8aa834dbd
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/505501
Reviewed-by: Samuel Rawlins <srawlins@google.com>
Commit-Queue: Brian Wilkerson <brianwilkerson@google.com>
Brian Wilkerson
739826d041