SI-10154 Fix implicit search regression for term-owned objects

A recent change  to fix lookup of companion implicits of term-owned
classes (#5550) caused a regression in the enclosed test case. The
previous approach of calling `Scope#lookup(companionName)` was
replaced by a lookup of the scope entry of the original name followed
by a narrower search lookup for the companion name, to ensure
that it was a true companion, and not just a same-named module
from defined at a different nested scope.

However, module class symbols are not themselves entered into
scopes, so the first part of the new scheme fails. We need to
add a special case modules here.

I've chosen to just call `.sourceModule` on module classes.
For module classes in the current run (all term owned symbols
will fall into this category), this amounts to using the value
of the field `ModuleClassSymbol#module`.

1 files changed, 11 insertions, 0 deletions

diff --git a/test/files/pos/t10154.scala b/test/files/pos/t10154.scala
new file mode 100644
index 0000000000..51616b71d6
--- /dev/null
+++ b/test/files/pos/t10154.scala
@@ -0,0 +1,11 @@
+trait Bar2[T]
+
+object Test2 {
+  def wrap {
+    object Foo {
+      implicit def fooBar: Bar2[Foo.type] = ???
+    }
+
+    implicitly[Bar2[Foo.type]]
+  }
+}