Create from Usage: Respect smart-casts when suggesting parameter type candidates

#KT-6781 Fixed

idea/testData/quickfix/createFromUsage/createFunction/call/afterSmartCastWithNullCheck.kt

@@ -0,0 +1,10 @@
+// "Create function 'foo'" "true"
+
+fun test(s: String?) {
+    if (s == null) return
+    foo(s)
+}
+
+fun foo(s: String) {
+    throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
+}