[JVM] Port line number tests to stepping framework.

Allow specifying JVM and JVM_IR as well as shared expectations.

Add the method name to the step.

Discard steps in synthetic methods.

compiler/testData/debug/stepping/class.kt

@@ -0,0 +1,35 @@
+// FILE: test.kt
+
+class A {
+    val prop = 1
+
+    fun foo() {
+        prop
+    }
+}
+
+fun box() {
+    val a = A()
+    a.prop
+    a.foo()
+}
+
+// TODO: The JVM_IR backend has an extra line number on the return. This causes line
+// three to be hit both on entry to the constructor and on exit after storing the
+// value of prop.
+
+// LINENUMBERS
+// test.kt:12 box
+// test.kt:3 <init>
+// test.kt:4 <init>
+// LINENUMBERS JVM_IR
+// test.kt:3 <init>
+// LINENUMBERS
+// test.kt:12 box
+// test.kt:13 box
+// test.kt:4 getProp
+// test.kt:13 box
+// test.kt:14 box
+// test.kt:7 foo
+// test.kt:8 foo
+// test.kt:15 box