- Inherited type declarations are in scope in Java code
 - For static innner classes, we need to check in the companion
module of each base classes.
 - Incorporate and accomodate test case from scala#6053
 - Tests to java code referring to module-class owned classes via companion class prefix

 Backport of scala#7671

 - Inherited type declarations are in scope in Java code
 - For static innner classes, we need to check in the companion
module of each base classes.
 - Incorporate and accomodate test case from scala#6053
 - Tests to java code referring to module-class owned classes via companion class prefix

 Backport of scala#7671

It's subsumed by Jason's improvements to name resolution in scala#7671.

The leak yielded spurious errors in mixed Scala/Java compilation (akka-http).

Also, pull up exemption for synthetic members from refchecks; it makes no
sense to bother the user about members synthesized by the compiler.

We could get early warnings this way, but eventually they'll pop up
as VerifyErrors...

It's subsumed by Jason's improvements to name resolution in scala#7671.

The leak yielded spurious errors in mixed Scala/Java compilation (akka-http).

It's subsumed by Jason's improvements to name resolution in scala#7671.

The leak yielded spurious errors in mixed Scala/Java compilation (akka-http).

(cherry picked from commit 8529be7)

Fixed in scala#7671, which was backported to 2.12.x in scala#7738

To find Scala companion mudule from Java in mixed sources,
we should strip module suffix `$`.
This provides workaround for scala#17255, but it requires some refinment to fix it
because not-fully-qualified type like the following example still fails
to compile due to missing symbol.

```java
package example;

public class Bar {
    private static final Foo$ MOD = Foo$.MODULE;
}
```

This is because `pre` in `javaFindMember` for `Foo` in the case above is `<root>`,
not `example` and therefore `pre.findMember` looks for `<root>.Foo` instead
of `example.Foo`.

I'm not sure whether the qualifier is intentionally dropped.

References
- scala#12884
- scala/scala#7671

To find Scala companion mudule from Java in mixed sources,
we should strip module suffix `$`.
This provides workaround for #17255, but it requires some refinment to fix it
because not-fully-qualified type like the following example still fails
to compile due to missing symbol.

```java
package example;

public class Bar {
    private static final Foo$ MOD = Foo$.MODULE;
}
```

This is because `pre` in `javaFindMember` for `Foo` in the case above is `<root>`,
not `example` and therefore `pre.findMember` looks for `<root>.Foo` instead
of `example.Foo`.

I'm not sure whether the qualifier is intentionally dropped.

References
- #12884
- scala/scala#7671

[Cherry-picked 22d98d6][modified]