[IR][tests] Update tests to reflect changes in partial linkage error messages

compiler/testData/klibABI/removeFunction/main/m.kt

@@ -1,31 +1,39 @@
 fun test1(): String {
-    try {
-        return qux(true)
+    return try {
+        qux(true)
     } catch(e: Throwable) {
-        if (e.isLinkageError("/exp_foo")) return "OK"
+        e.checkLinkageError("function exp_foo can not be called")
     }
-
-    return "FAIL5"
 }
 
 fun test2(): String = qux(false)
 
 fun test3(): String {
-    try {
-        return qux2(true)
+    return try {
+        qux2(true)
     } catch(e: Throwable) {
-        if (e.isLinkageError("/A.exp_foo")) return "OK"
+        e.checkLinkageError("function exp_foo can not be called")
     }
-
-    return "FAIL6"
 }
 
 fun test4(): String = qux2(false)
 
-fun box(): String {
-    val result = test1() + test2() + test3() + test4()
-    return if (result == "OKOKOKOK") "OK" else result
+fun box() = checkResults(test1(), test2(), test3(), test4())
+
+private fun Throwable.checkLinkageError(prefix: String): String {
+    if (this::class.simpleName != "IrLinkageError") return "Unexpected throwable: ${this::class}"
+
+    val expectedMessagePrefix = "$prefix because it uses unlinked symbols"
+    val actualMessage = message.orEmpty()
+
+    return if (actualMessage.startsWith(expectedMessagePrefix))
+        "OK"
+    else
+        "EXPECTED: $expectedMessagePrefix, ACTUAL: $actualMessage"
 }
 
-private fun Throwable.isLinkageError(symbolName: String): Boolean =
-    this::class.simpleName == "IrLinkageError" && message?.startsWith("Unlinked IR symbol $symbolName|") == true
+private fun checkResults(vararg results: String): String = when {
+    results.isEmpty() -> "no results to check"
+    results.all { it == "OK" } -> "OK"
+    else -> results.joinToString("\n")
+}