functional type: find common super type of intersection type's conjuncts (IDEA-144145)

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/functionalInterface/IntersectionTypeWithSameBaseInterfaceInConjuncts.java

@@ -0,0 +1,12 @@
+interface Z {
+  void m();
+}
+
+interface X extends Z {}
+interface Y extends Z {}
+
+class Test {
+  {
+    ((X & <caret>Y) () -> {}).m();
+  }
+}