add type cast intention for poly expressions (IDEA-188731)

inference errors on poly expressions are not propagated to the expected type (variable declaration, return statement, etc) like for standalone expressions: dedicated intentions should be registered

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/addTypeCast/afterReturnTypeCaseInferenceError.java

@@ -0,0 +1,13 @@
+// "Cast to 'B'" "true"
+import java.util.*;
+
+class A { }
+
+class B extends A {
+    public B getStrings() {
+        return (B) getFirstItem(new ArrayList<A>());
+    }
+
+    public static <T> T getFirstItem(Set<T> items) { return null; }
+    public static <T> T getFirstItem(List<T> items) { return null; }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/addTypeCast/beforeReturnTypeCaseInferenceError.java

@@ -0,0 +1,13 @@
+// "Cast to 'B'" "true"
+import java.util.*;
+
+class A { }
+
+class B extends A {
+    public B getStrings() {
+        return get<caret>FirstItem(new ArrayList<A>());
+    }
+
+    public static <T> T getFirstItem(Set<T> items) { return null; }
+    public static <T> T getFirstItem(List<T> items) { return null; }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/addTypeCast/beforeReturnTypeCaseInferenceErrorIncompatibleTypes.java

@@ -0,0 +1,13 @@
+// "Cast to 'B'" "false"
+import java.util.*;
+
+class A { }
+
+class B extends A {
+    public B getStrings() {
+        return get<caret>FirstItem(new ArrayList<A>());
+    }
+
+    public static <T> T            getFirstItem(Set<T> items) { return null; }
+    public static <T> ArrayList<T> getFirstItem(List<T> items) { return null; }
+}