new inference: reject varargs as method reference target

(cherry picked from commit 77017d7790b78c5bb20c591e2588c1eccd0f96d7)

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/newMethodRef/AmbiguityVarargs.java

@@ -0,0 +1,20 @@
+class Test {
+
+  interface IntMapper {
+    int map();
+  }
+
+  interface LongMapper {
+    long map();
+  }
+
+  void m(IntMapper im1, IntMapper... im) { }
+  void m(LongMapper... lm) { }
+  
+  {
+      m<error descr="Ambiguous method call: both 'Test.m(IntMapper, IntMapper...)' and 'Test.m(LongMapper...)' match">(this ::ii)</error>;
+  }
+
+  int ii() {return 0;}
+
+}