try to use bounds in type inference

if some parameters are unknown

compiler/testData/diagnostics/tests/inference/upperBounds/useBoundsIfUnknownParameters.kt

@@ -0,0 +1,11 @@
+package Hello
+
+open class Base<T>
+class StringBase : Base<String>()
+
+class Client<T, X: Base<T>>(x: X)
+
+fun test() {
+    val c = Client(StringBase()) // Type inference fails here for T.
+    val <!UNUSED_VARIABLE!>i<!> : Int = <!TYPE_MISMATCH!>c<!>
+}