JVM BE: Add more tests for default arguments

- Inline class parameters should not be boxed.
- Empty vararg parameters should not allocate an empty array.

compiler/testData/codegen/bytecodeText/defaultArguments/noEmptyArray.kt

@@ -0,0 +1,9 @@
+// IGNORE_BACKEND: JVM_IR
+
+// There is one ANEWARRAY instruction here, to generate the default parameter value.
+fun default(vararg s: String = arrayOf("OK")) = s[0]
+
+// This call on the other hand shouldn't allocate anything.
+fun callDefault() = default()
+
+// 1 ANEWARRAY

compiler/testData/codegen/bytecodeText/inlineClasses/defaultParametersDontBox.kt

@@ -0,0 +1,23 @@
+// LANGUAGE: +InlineClasses
+// IGNORE_BACKEND: JVM_IR
+// FILE: classes.kt
+
+inline class A(val i: Int)
+inline class B(val a: A)
+
+// FILE: test.kt
+
+fun defaultA(a: A = A(1)) = a.i
+fun defaultB(b: B = B(A(1))) = b.a.i
+
+fun box(): String {
+    if (defaultA() != 1) return "Fail 1"
+    if (defaultB() != 1) return "Fail 2"
+    return "OK"
+}
+
+// @TestKt.class:
+// 0 B.box-impl
+// 0 A.box-impl
+// 0 B.unbox-impl
+// 0 A.unbox-impl