JvmDefault. Allow non default inheritance with special flag

#KT-47000

compiler/testData/codegen/box/jvm8/defaults/nonDefaultInheritance/simple2.kt

@@ -0,0 +1,39 @@
+// TARGET_BACKEND: JVM
+// IGNORE_BACKEND_FIR: JVM_IR
+// FULL_JDK
+// JVM_TARGET: 1.8
+// WITH_RUNTIME
+// MODULE: lib
+// !JVM_DEFAULT_MODE: all
+// FILE: Foo.kt
+
+interface Foo {
+    fun toOverride(): List<String> = null!!
+    
+    fun nonOverride(): List<String> = Thread.currentThread().getStackTrace().map { it.className + "." + it.methodName }
+}
+
+// MODULE: main(lib)
+// !JVM_DEFAULT_MODE: disable
+// !JVM_DEFAULT_ALLOW_NON_DEFAULT_INHERITANCE
+// FILE: main.kt
+
+interface Derived : Foo {
+    override fun toOverride() = Thread.currentThread().getStackTrace().map { it.className + "." + it.methodName }
+}
+
+class DerivedClass : Derived 
+
+
+fun box(): String {
+    val override = DerivedClass().toOverride()
+    if (override[1] != "Derived\$DefaultImpls.toOverride") return "fail 1: ${override[1]}"
+    if (override[2] != "DerivedClass.toOverride") return "fail 2: ${override[2]}"
+    if (override[3] != "MainKt.box") return "fail 3: ${override[3]}"
+
+    val nonOverride = DerivedClass().nonOverride()
+    if (nonOverride[1] != "Foo.nonOverride") return "fail 3: ${nonOverride[1]}"
+    if (nonOverride[2] != "MainKt.box") return "fail 4: ${nonOverride[2]}"
+
+    return "OK"
+}