Generate line numbers for closing '}' in 'init {}' blocks (KT-12787)

compiler/testData/lineNumber/custom/initBlocks.kt

@@ -0,0 +1,34 @@
+class Foo {
+    var a: String
+
+    init {
+        a = x()
+    }
+}
+
+class Bar {
+    init {
+        val a = 5
+    }
+
+    init {
+        val b = 2
+    }
+}
+
+class Boo {
+    init {
+        val a = 5
+    }
+
+    val x = x()
+
+    init {
+        val b = 2
+    }
+}
+
+fun x() = ""
+
+// IGNORE_BACKEND: JVM_IR
+// 2 2 1 5 6 9 11 12 15 16 24 19 21 22 24 27 28 31