deeply eliminate wildcards as they may appear during inference in wildcard's bounds

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

@@ -0,0 +1,14 @@
+import java.util.Arrays;
+import java.util.List;
+
+class FunctionReferenceTest {
+  public static void main(String[] args) {
+    List<String> strings = Arrays.asList();
+
+    int sum = strings.stream().mapToInt(CharSequence::length).sum();
+
+    List<? extends CharSequence> sequences = strings;
+
+    sum = sequences.stream().mapToInt(CharSequence::length).sum();
+  }
+}