Introduce support for plugin-defined intrinsics in old JVM backend:

(Old is created first because all intrinsics emit bytecode anyway)

Provide intrinsic for serializer<T>() function so it won't
invoke typeOf() construction and KType->KSerializer conversion
making it fast and truly reflectionless

Add support for recalculating stack size in plugin-defined intrinsics
since it is needed for correct work:
Unify method for recalculating stack size with existing typeOf intrinsic

Add testdata for IR for future intrinsic in IR

plugins/kotlinx-serialization/tests-gen/org/jetbrains/kotlinx/serialization/runners/SerializationAsmLikeInstructionsListingTestGenerated.java

@@ -37,6 +37,12 @@ public class SerializationAsmLikeInstructionsListingTestGenerated extends Abstra
         runTest("plugins/kotlinx-serialization/testData/codegen/Delegated.kt");
     }
 
+    @Test
+    @TestMetadata("Intrinsics.kt")
+    public void testIntrinsics() throws Exception {
+        runTest("plugins/kotlinx-serialization/testData/codegen/Intrinsics.kt");
+    }
+
     @Test
     @TestMetadata("Sealed.kt")
     public void testSealed() throws Exception {

plugins/kotlinx-serialization/tests-gen/org/jetbrains/kotlinx/serialization/runners/SerializationIrAsmLikeInstructionsListingTestGenerated.java

@@ -37,6 +37,12 @@ public class SerializationIrAsmLikeInstructionsListingTestGenerated extends Abst
         runTest("plugins/kotlinx-serialization/testData/codegen/Delegated.kt");
     }
 
+    @Test
+    @TestMetadata("Intrinsics.kt")
+    public void testIntrinsics() throws Exception {
+        runTest("plugins/kotlinx-serialization/testData/codegen/Intrinsics.kt");
+    }
+
     @Test
     @TestMetadata("Sealed.kt")
     public void testSealed() throws Exception {