[FIR] Handle fully qualified expressions separately in tower resolver

compiler/testData/diagnostics/tests/regressions/kt459.fir.kt

@@ -1,7 +1,7 @@
 // KT-459 Type argument inference fails when class names are fully qualified
 
 fun test() {
-  val attributes : java.util.HashMap<String, String> = java.util.<!UNRESOLVED_REFERENCE!>HashMap<!>() // failure!
+  val attributes : java.util.HashMap<String, String> = java.util.HashMap() // failure!
   attributes["href"] = "1" // inference fails, but it shouldn't
 }
 

compiler/testData/diagnostics/tests/regressions/kt549.fir.kt

@@ -3,9 +3,9 @@
 package demo
 
   fun <T> filter(list : Array<T>, filter :  (T) -> Boolean) : List<T> {
-    val answer = java.util.<!UNRESOLVED_REFERENCE!>ArrayList<!><T>();
+    val answer = java.util.ArrayList<T>();
     for (l in list) {
-      if (filter(l)) answer.<!UNRESOLVED_REFERENCE!>add<!>(l)
+      if (filter(l)) answer.add(l)
     }
     return answer;
   }