KT-948 Make type inference work with sure()/!!

!! part fixed

compiler/testData/diagnostics/tests/inference/regressions/kt948.kt

@@ -0,0 +1,18 @@
+package a
+
+import java.util.*
+
+fun <T> emptyList() : List<T>? = ArrayList<T>()
+
+fun foo() {
+    // type arguments shouldn't be required
+    val <!UNUSED_VARIABLE!>l<!> : List<Int> = emptyList()!!
+    val <!UNUSED_VARIABLE!>l1<!> = <!TYPE_INFERENCE_NO_INFORMATION_FOR_PARAMETER!>emptyList<!>()!!
+
+    emptyList()!! : List<Int>
+    emptyList() : List<Int>?
+
+    doWithList(emptyList()!!)
+}
+
+fun doWithList(list: List<Int>) = list