Update with latest scalac 2.12.5

jvican · jvican · commit 62322ca25a9a · 2018-01-22T00:55:24.000+01:00
It includes the classloading changes in scala/scala-dev#458.
diff --git a/scalac b/scalac
@@ -1 +1 @@
-Subproject commit 9b4554dd5893a5cb860b1ecc8f32c4a669a2e29a
+Subproject commit f18e3c59fdbb1a412c37d4d85def6f766f11cfa2
