use boxed type instead of expected primitive when NULL type is calculated

this allows int -> Integer signature changes when null is passed where primitive is expected (IDEA-164942)

java/java-impl/src/com/intellij/refactoring/util/RefactoringUtil.java

@@ -393,6 +393,9 @@ public class RefactoringUtil {
       ExpectedTypeInfo[] infos = ExpectedTypesProvider.getExpectedTypes(expr, false);
       if (infos.length == 1) {
         type = infos[0].getType();
+        if (type instanceof PsiPrimitiveType) {
+          type = ((PsiPrimitiveType)type).getBoxedType(expr);
+        }
       }
       else {
         type = factory.createTypeByFQClassName(CommonClassNames.JAVA_LANG_OBJECT, expr.getResolveScope());

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/changeMethodSignatureFromUsage/afterToBoxedType.java

@@ -0,0 +1,5 @@
+// "Change 1st parameter of method 'bar' from 'int' to 'Integer'" "true"
+ public class Bar {
+     void bar(Integer i) { }
+     { bar(null);}
+ }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/changeMethodSignatureFromUsage/beforeToBoxedType.java

@@ -0,0 +1,5 @@
+// "Change 1st parameter of method 'bar' from 'int' to 'Integer'" "true"
+ public class Bar {
+     void bar(int i) { }
+     { bar(n<caret>ull);}
+ }