Disable running checkers by default (#4644)

* Make checkers be disabled by default

* Allow running checkers in test launcher

kotlin-native/backend.native/tests/runtime/basic/cleaner_leak.kt

@@ -1,24 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
- * that can be found in the LICENSE file.
- */
-@file:OptIn(ExperimentalStdlibApi::class)
-
-import kotlin.test.*
-
-import kotlin.native.internal.*
-
-// This cleaner won't be run, because it's deinitialized with globals after
-// cleaners are disabled.
-val globalCleaner = createCleaner(42) {
-    println(it)
-}
-
-fun main() {
-    // Cleaner holds onto a finalization lambda. If it doesn't get executed,
-    // the memory will leak. Suppress memory leak checker to check for cleaners
-    // leak only.
-    Platform.isMemoryLeakCheckerActive = false
-    // Make sure cleaner is initialized.
-    assertNotNull(globalCleaner)
-}

kotlin-native/backend.native/tests/runtime/basic/cleaner_leak_with_checker.kt

@@ -16,10 +16,6 @@ val globalCleaner = createCleaner(42) {
 }
 
 fun main() {
-    // Cleaner holds onto a finalization lambda. If it doesn't get executed,
-    // the memory will leak. Suppress memory leak checker to check for cleaners
-    // leak only.
-    Platform.isMemoryLeakCheckerActive = false
     Platform.isCleanersLeakCheckerActive = true
     // Make sure cleaner is initialized.
     assertNotNull(globalCleaner)

kotlin-native/backend.native/tests/runtime/basic/cleaner_leak_without_checker.kt

@@ -16,11 +16,6 @@ val globalCleaner = createCleaner(42) {
 }
 
 fun main() {
-    // Cleaner holds onto a finalization lambda. If it doesn't get executed,
-    // the memory will leak. Suppress memory leak checker to check for cleaners
-    // leak only.
-    Platform.isMemoryLeakCheckerActive = false
-    Platform.isCleanersLeakCheckerActive = false
     // Make sure cleaner is initialized.
     assertNotNull(globalCleaner)
 }