FIR IDE: Unwrap nullable types

idea/testData/shortenRefsFir/types/ParameterTypeNullableType.kt

@@ -0,0 +1,6 @@
+// FIR_COMPARISON
+package test
+
+class T
+
+<selection>fun foo(t: test.T???) {}</selection>

idea/testData/shortenRefsFir/types/ParameterTypeNullableType.kt.after

@@ -0,0 +1,6 @@
+// FIR_COMPARISON
+package test
+
+class T
+
+fun foo(t: T???) {}