FIR: report lowering time from JvmIrCodegenFactory

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmIrCodegenFactory.kt

@@ -49,6 +49,7 @@ class JvmIrCodegenFactory(private val phaseConfig: PhaseConfig) : CodegenFactory
         val irProviders: List<IrProvider>,
         val extensions: JvmGeneratorExtensions,
         val backendExtension: JvmBackendExtension,
+        val notifyCodegenStart: () -> Unit,
     )
 
     override fun generateModule(state: GenerationState, files: Collection<KtFile>) {
@@ -158,6 +159,7 @@ class JvmIrCodegenFactory(private val phaseConfig: PhaseConfig) : CodegenFactory
             irProviders,
             extensions,
             JvmBackendExtension.Default,
+            {},
         )
     }
 
@@ -173,7 +175,7 @@ class JvmIrCodegenFactory(private val phaseConfig: PhaseConfig) : CodegenFactory
     }
 
     fun doGenerateFilesInternal(input: JvmIrBackendInput) {
-        val (state, irModuleFragment, symbolTable, sourceManager, phaseConfig, irProviders, extensions, backendExtension) = input
+        val (state, irModuleFragment, symbolTable, sourceManager, phaseConfig, irProviders, extensions, backendExtension, notifyCodegenStart) = input
         val context = JvmBackendContext(
             state, sourceManager, irModuleFragment.irBuiltins, irModuleFragment,
             symbolTable, phaseConfig, extensions, backendExtension
@@ -189,6 +191,8 @@ class JvmIrCodegenFactory(private val phaseConfig: PhaseConfig) : CodegenFactory
 
         JvmLower(context).lower(irModuleFragment)
 
+        notifyCodegenStart()
+
         for (generateMultifileFacade in listOf(true, false)) {
             for (irFile in irModuleFragment.files) {
                 // Generate multifile facades first, to compute and store JVM signatures of const properties which are later used
@@ -221,10 +225,11 @@ class JvmIrCodegenFactory(private val phaseConfig: PhaseConfig) : CodegenFactory
         sourceManager: PsiSourceManager,
         extensions: JvmGeneratorExtensions,
         backendExtension: JvmBackendExtension,
+        notifyCodegenStart: () -> Unit
     ) {
         val irProviders = configureBuiltInsAndgenerateIrProvidersInFrontendIRMode(irModuleFragment, symbolTable, extensions)
         doGenerateFilesInternal(
-            JvmIrBackendInput(state, irModuleFragment, symbolTable, sourceManager, phaseConfig, irProviders, extensions, backendExtension)
+            JvmIrBackendInput(state, irModuleFragment, symbolTable, sourceManager, phaseConfig, irProviders, extensions, backendExtension, notifyCodegenStart)
         )
     }