captured of non-proper wildcard can't be used as solving bound (IDEA-180042)

java/java-psi-impl/src/com/intellij/psi/impl/source/resolve/graphInference/InferenceSession.java

@@ -1240,7 +1240,9 @@ public class InferenceSession {
 
         //restore captured wildcard from method return type when no additional constraints were inferred
         //to preserve equality of type arguments
-        if (capturedWildcard != null && capturedWildcard.getUpperBound().equals(getUpperBound(aClass))) {
+        if (capturedWildcard != null &&
+            capturedWildcard.getUpperBound().equals(getUpperBound(aClass)) &&
+            isProperType(capturedWildcard.getWildcard())) {
           eqBound = capturedWildcard;
         }
       }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/lambda/graphInference/RestoreCapturedWildcardsInReturnTypesWhenNoAdditionalConstraintsDetected.java

@@ -43,3 +43,14 @@ class Test {
     return list.stream().collect(Collectors.toCollection(() -> create()));
   }
 }
+
+
+class TestWithNonProperTypeBeforeCapture {
+  {
+    Set<? super List<String>> set = foo();
+  }
+
+  private <K> Set<? super List<K>> foo() { //#CAP<? super List<K>> is not proper, can't be used as eq bound
+    return null;
+  }
+}