KT-418 Make 1.?plus(2) have type Int

compiler/frontend/src/org/jetbrains/jet/lang/types/expressions/BasicExpressionTypingVisitor.java

@@ -441,7 +441,9 @@ public class BasicExpressionTypingVisitor extends ExpressionTypingVisitor {
         //TODO move further
         if (expression.getOperationSign() == JetTokens.SAFE_ACCESS) {
             if (selectorReturnType != null && !selectorReturnType.isNullable() && !JetStandardClasses.isUnit(selectorReturnType)) {
-                selectorReturnType = TypeUtils.makeNullable(selectorReturnType);
+                if (receiverType.isNullable()) {
+                    selectorReturnType = TypeUtils.makeNullable(selectorReturnType);
+                }
             }
         }
 

compiler/testData/checkerWithErrorTypes/quick/SafeCallNonNullReceiver.jet

@@ -0,0 +1,6 @@
+// http://youtrack.jetbrains.net/issue/KT-418
+
+fun ff() {
+    val i: Int = 1
+    val a: Int = i<!UNNECESSARY_SAFE_CALL!>?.<!>plus(2)
+}