[JVM_IR] Generate line numbers and nops for init blocks.

This seems to be what JVM does and it allows you to set a
breakpoint on the init line.

compiler/testData/debug/stepping/initBlocks.kt

@@ -51,10 +51,8 @@ fun box() {
     Zoo()
 }
 
-// IGNORE_BACKEND: JVM_IR
-// The JVM_IR does not generate code that will break on the line
-// containing the `init`, nor the exit from the `init`. It only
-// contains lines for the contents of the init blocks.
+// JVM_IR has an extra step back to the line of the class
+// declaration for the return in the constructor.
 
 // LINENUMBERS
 // test.kt:48 box
@@ -64,6 +62,9 @@ fun box() {
 // test.kt:45 x
 // test.kt:7 <init>
 // test.kt:8 <init>
+// LINENUMBERS JVM_IR
+// test.kt:3 <init>
+// LINENUMBERS
 // test.kt:48 box
 // test.kt:49 box
 // test.kt:11 <init>
@@ -73,6 +74,9 @@ fun box() {
 // test.kt:16 <init>
 // test.kt:17 <init>
 // test.kt:18 <init>
+// LINENUMBERS JVM_IR
+// test.kt:11 <init>
+// LINENUMBERS
 // test.kt:49 box
 // test.kt:50 box
 // test.kt:21 <init>
@@ -85,6 +89,9 @@ fun box() {
 // test.kt:28 <init>
 // test.kt:29 <init>
 // test.kt:30 <init>
+// LINENUMBERS JVM_IR
+// test.kt:21 <init>
+// LINENUMBERS
 // test.kt:50 box
 // test.kt:51 box
 // test.kt:33 <init>
@@ -94,5 +101,8 @@ fun box() {
 // test.kt:39 <init>
 // test.kt:40 <init>
 // test.kt:42 <init>
+// LINENUMBERS JVM_IR
+// test.kt:33 <init>
+// LINENUMBERS
 // test.kt:51 box
 // test.kt:52 box

compiler/testData/debug/stepping/initBlocksCompanion.kt

@@ -0,0 +1,52 @@
+// FILE: test.kt
+
+class A {
+    companion object {
+        val s: String
+
+        init {
+            s = "OK"
+        }
+
+        val x = x()
+
+        init { val a = 32 }
+
+        init {
+            val b = 42
+        }
+
+        init
+        {
+            val c = 43
+        }
+    }
+}
+
+fun x() = ""
+
+fun box() {
+    A.x
+    A.s
+}
+
+// JVM backend has extra steps for getX and getS.
+
+// TODO: since these tests operate as step-into, we do not get any steps
+// in the <clinit> for the companion object. Maybe extend the test infrastructure
+// with directives to set break points in order to test this.
+
+// LINENUMBERS
+// test.kt:29 box
+// test.kt:11 getX
+// LINENUMBERS JVM
+// test.kt:11 getX
+// LINENUMBERS
+// test.kt:29 box
+// test.kt:30 box
+// test.kt:5 getS
+// LINENUMBERS JVM
+// test.kt:5 getS
+// LINENUMBERS
+// test.kt:30 box
+// test.kt:31 box