[FIR] Support type code fragments in 'PsiRawFirBuilder'

For type code fragments, which essentially contain a single type
reference, we add a single statement 'null is Type'.

^KT-61332 Fixed

compiler/fir/raw-fir/psi2fir/src/org/jetbrains/kotlin/fir/builder/PsiRawFirBuilder.kt

@@ -47,6 +47,7 @@ import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.psiUtil.*
 import org.jetbrains.kotlin.psi.stubs.KotlinFileStub
 import org.jetbrains.kotlin.psi.stubs.elements.KtStubElementTypes
+import org.jetbrains.kotlin.types.ConstantValueKind
 import org.jetbrains.kotlin.types.Variance
 import org.jetbrains.kotlin.types.expressions.OperatorConventions
 import org.jetbrains.kotlin.util.OperatorNameConventions
@@ -1373,6 +1374,7 @@ open class PsiRawFirBuilder(
                         when (file) {
                             is KtExpressionCodeFragment -> file.getContentElement()?.toFirBlock() ?: buildEmptyExpressionBlock()
                             is KtBlockCodeFragment -> configureBlockWithoutBuilding(file.getContentElement()).build()
+                            is KtTypeCodeFragment -> convertTypeCodeFragmentBlock(file)
                             else -> error("Unexpected code fragment type: ${file::class}")
                         }
                     }
@@ -1380,6 +1382,18 @@ open class PsiRawFirBuilder(
             }
         }
 
+        private fun convertTypeCodeFragmentBlock(file: KtTypeCodeFragment): FirBlock {
+            return buildBlock {
+                statements += buildTypeOperatorCall {
+                    operation = FirOperation.IS
+                    conversionTypeRef = file.getContentElement().toFirOrErrorType()
+                    argumentList = buildUnaryArgumentList(
+                        buildLiteralExpression(source = null, ConstantValueKind.Null, value = null, setType = false)
+                    )
+                }
+            }
+        }
+
         override fun visitScript(script: KtScript, data: FirElement?): FirElement {
             val ktFile = script.containingKtFile
             val fileName = ktFile.name