[K/N] Refactor unhandled exception handling API

* Do not reset unhandled exception hook
* Add processUnhandledException to perform default unhandled exception
  processing
* Add terminateWithUnhandledException to report the unhandled exception
  and terminate the program
* Use the default unhandled exception processing in entrypoint, interop
  boundaries and in Worker.executeAfter
* Add -Xworker-exception-handling to control exception processing of
  Worker.executeAfter. By default its the old behaviour with the old MM,
  and new behaviour with the new MM.

kotlin-native/backend.native/tests/runtime/exceptions/custom_hook_get.kt

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2010-2021 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.concurrent.*
+
+fun main() {
+    val exceptionHook = { _: Throwable ->
+        println("Hook")
+    }.freeze()
+
+    val oldHook = setUnhandledExceptionHook(exceptionHook)
+    assertNull(oldHook)
+    val hook1 = getUnhandledExceptionHook()
+    assertEquals(exceptionHook, hook1)
+    val hook2 = getUnhandledExceptionHook()
+}

kotlin-native/backend.native/tests/runtime/exceptions/custom_hook_memory_leak.kt

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2010-2021 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.
+ */
+import kotlin.test.*
+
+import kotlin.native.concurrent.*
+
+data class C(val x: Int)
+
+fun main() {
+    Platform.isMemoryLeakCheckerActive = true
+
+    val c = C(42)
+    setUnhandledExceptionHook({ _: Throwable ->
+        println("Hook ${c.x}")
+    }.freeze())
+
+    throw Error("an error")
+}

kotlin-native/backend.native/tests/runtime/exceptions/custom_hook_no_reset.kt

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2010-2021 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.concurrent.*
+
+fun customExceptionHook(throwable: Throwable) {
+    println("Hook called")
+    assertEquals(::customExceptionHook, getUnhandledExceptionHook())
+}
+
+fun main() {
+    setUnhandledExceptionHook((::customExceptionHook).freeze())
+
+    throw Error("some error")
+}

kotlin-native/backend.native/tests/runtime/exceptions/custom_hook_terminate.kt

@@ -0,0 +1,18 @@
+/*
+ * Copyright 2010-2021 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.concurrent.*
+
+fun main() {
+    setUnhandledExceptionHook({ t: Throwable ->
+        println("Hook called")
+        terminateWithUnhandledException(t)
+    }.freeze())
+
+    throw Error("some error")
+}

kotlin-native/backend.native/tests/runtime/exceptions/custom_hook_terminate_unhandled_exception.kt

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2010-2021 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.concurrent.*
+
+fun main() {
+    setUnhandledExceptionHook({ t: Throwable ->
+        println("Hook called")
+        terminateWithUnhandledException(t)
+    }.freeze())
+
+    val exception = Error("some error")
+    processUnhandledException(exception)
+    println("Not going to happen")
+}

kotlin-native/backend.native/tests/runtime/exceptions/custom_hook_throws.kt

@@ -0,0 +1,18 @@
+/*
+ * Copyright 2010-2021 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.
+ */
+import kotlin.test.*
+
+import kotlin.native.concurrent.*
+
+fun customExceptionHook(throwable: Throwable) {
+    println("Hook called")
+    throw Error("another error")
+}
+
+fun main() {
+    setUnhandledExceptionHook((::customExceptionHook).freeze())
+
+    throw Error("some error")
+}

kotlin-native/backend.native/tests/runtime/exceptions/custom_hook_unhandled_exception.kt

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2010-2021 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.concurrent.*
+
+fun main() {
+    val called = AtomicInt(0)
+    setUnhandledExceptionHook({ _: Throwable ->
+        called.value = 1
+    }.freeze())
+
+    val exception = Error("some error")
+    processUnhandledException(exception)
+    assertEquals(1, called.value)
+}

kotlin-native/backend.native/tests/runtime/exceptions/terminate.kt

@@ -0,0 +1,12 @@
+/*
+ * Copyright 2010-2021 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.*
+
+fun main() {
+    val exception = Error("some error")
+    terminateWithUnhandledException(exception)
+}

kotlin-native/backend.native/tests/runtime/exceptions/unhandled_exception.kt

@@ -0,0 +1,12 @@
+/*
+ * Copyright 2010-2021 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.*
+
+fun main() {
+    val exception = Error("some error")
+    processUnhandledException(exception)
+}