[trivial] improving consistency between javac vs. ecj output

wasn't worth an issue on the tracker: javac and ecj handlers for static constructors would differ; ecjs would specify the return type and constructor invocation using fully qualified types, whereas the handler for javac did not.

test/transform/resource/after-delombok/ConstructorInner.java

@@ -0,0 +1,11 @@
+class ConstructorInner {
+	static class Inner {
+		@java.lang.SuppressWarnings("all")
+		private Inner() {
+		}
+		@java.lang.SuppressWarnings("all")
+		public static ConstructorInner.Inner of() {
+			return new ConstructorInner.Inner();
+		}
+	}
+}