kotlinp: use JVM_IR backend for compiling tests

Also, test optimized delegated properties.

libraries/tools/kotlinp/testData/LocalDelegatedProperties.txt

@@ -22,13 +22,6 @@ public final class Class : kotlin/Any {
 
   // module name: test-module
 }
-// Class$f$1.class
-// ------------------------------------------
-lambda {
-
-  // signature: invoke()V
-  local final fun g(): kotlin/Unit
-}
 // Delegate.class
 // ------------------------------------------
 public final class Delegate<T#0 /* T */> : kotlin/Any {

libraries/tools/kotlinp/testData/Properties.kt

@@ -8,5 +8,7 @@ class C(val constructorParam: String = "") {
 
     val <T : Number> T.delegated: List<Nothing> by null
 
+    val withOptimizedDelegate by C::getterOnlyVal
+
     operator fun Nothing?.getValue(x: Any?, y: Any?) = emptyList<Nothing>()
 }

libraries/tools/kotlinp/testData/Properties.txt

@@ -30,6 +30,11 @@ public final class C : kotlin/Any {
     public final get
     public final set
 
+  // getter: getWithOptimizedDelegate()D
+  // synthetic method for delegate: getWithOptimizedDelegate$delegate(LC;)Ljava/lang/Object;
+  public final /* delegated */ val withOptimizedDelegate: kotlin/Double
+    public final /* non-default */ get
+
   // field: delegated$delegate:Ljava/lang/Void;
   // getter: getDelegated(Ljava/lang/Number;)Ljava/util/List;
   public final /* delegated */ val <T#0 /* T */ : kotlin/Number> T#0.delegated: kotlin/collections/List<kotlin/Nothing>