Make fields representing variables in coroutines non-volatile

#KT-14636 Fixed

compiler/testData/codegen/bytecodeListing/coroutineFields.kt

@@ -0,0 +1,23 @@
+class Controller {
+    suspend fun suspendHere(x: Continuation<String>) {
+        x.resume("OK")
+    }
+}
+
+fun builder(coroutine c: Controller.(String, Long) -> Continuation<Unit>) {
+    c(Controller(), "", 2L).resume(Unit)
+}
+
+fun box(): String {
+    var result = ""
+
+    builder { x, y ->
+        val z = ""
+        val u = 1L
+        result = suspendHere()
+
+        result += z + u
+    }
+
+    return result
+}

compiler/testData/codegen/bytecodeListing/coroutineFields.txt

@@ -0,0 +1,27 @@
+@kotlin.Metadata
+public final class Controller {
+    public method <init>(): void
+    public final method suspendHere(@org.jetbrains.annotations.NotNull p0: kotlin.coroutines.Continuation): void
+}
+
+@kotlin.Metadata
+final class CoroutineFieldsKt$box$1 {
+    synthetic final field $result: kotlin.jvm.internal.Ref$ObjectRef
+    private field J$0: long
+    private field L$0: java.lang.Object
+    private field L$1: java.lang.Object
+    private final field p$0: java.lang.String
+    private final field p$1: long
+    inner class CoroutineFieldsKt$box$1
+    method <init>(p0: kotlin.jvm.internal.Ref$ObjectRef): void
+    protected final method doResume(@org.jetbrains.annotations.Nullable p0: java.lang.Object, @org.jetbrains.annotations.Nullable p1: java.lang.Throwable): void
+    public final @org.jetbrains.annotations.NotNull method invoke(@org.jetbrains.annotations.NotNull p0: Controller, @org.jetbrains.annotations.NotNull p1: java.lang.String, p2: long): kotlin.coroutines.Continuation
+    public synthetic method invoke(p0: java.lang.Object, p1: java.lang.Object, p2: java.lang.Object): java.lang.Object
+}
+
+@kotlin.Metadata
+public final class CoroutineFieldsKt {
+    inner class CoroutineFieldsKt$box$1
+    public final static @org.jetbrains.annotations.NotNull method box(): java.lang.String
+    public final static method builder(@org.jetbrains.annotations.NotNull p0: kotlin.jvm.functions.Function3): void
+}