unchecked warnings: check poly conditional branches in context of target type (IDEA-199615)

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/advHighlighting8/UncheckedWarningForPolyConditional.java

@@ -0,0 +1,11 @@
+class MyTest {
+    interface I<T> {
+        void m();
+    }
+
+    private final I<String> i;
+    
+    public MyTest(I i) {
+        this.i = i == null ? () -> {} : <warning descr="Unchecked assignment: 'MyTest.I' to 'MyTest.I<java.lang.String>'">i</warning>;
+    }
+}