Add test on isNullOrEmpty-like contract

Currently, behavior is undesired, see KT-27241

compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/valueOfContractedFunctionIngored.kt

@@ -0,0 +1,11 @@
+// !LANGUAGE: +AllowContractsForCustomFunctions +UseReturnsEffect
+// !USE_EXPERIMENTAL: kotlin.contracts.ExperimentalContracts
+// !DIAGNOSTICS: -INVISIBLE_REFERENCE -INVISIBLE_MEMBER
+
+import kotlin.contracts.*
+
+fun f3(value: String?) {
+    if (<!USELESS_IS_CHECK!>!value.isNullOrEmpty() is Boolean<!>) {
+        <!DEBUG_INFO_SMARTCAST!>value<!>.length
+    }
+}

compiler/testData/diagnostics/testsWithStdLib/contracts/smartcasts/valueOfContractedFunctionIngored.txt

@@ -0,0 +1,4 @@
+package
+
+public fun myIf(/*0*/ cond: kotlin.Boolean): kotlin.Any
+public fun test(/*0*/ x: kotlin.Any?): kotlin.Unit