[PLUGIN API] Drop PureIrGenerationExtension

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/KotlinCoreEnvironment.kt

@@ -550,8 +550,6 @@ class KotlinCoreEnvironment private constructor(
             CollectAdditionalSourcesExtension.registerExtensionPoint(project)
             ExtraImportsProviderExtension.registerExtensionPoint(project)
             IrGenerationExtension.registerExtensionPoint(project)
-            @Suppress("DEPRECATION_ERROR")
-            org.jetbrains.kotlin.backend.common.extensions.PureIrGenerationExtension.registerExtensionPoint(project)
             ScriptEvaluationExtension.registerExtensionPoint(project)
             ShellExtension.registerExtensionPoint(project)
             TypeResolutionInterceptor.registerExtensionPoint(project)

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/extensions/IrGenerationExtension.kt

@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.backend.common.extensions
 
-import org.jetbrains.kotlin.backend.common.CommonBackendContext
 import org.jetbrains.kotlin.extensions.ProjectExtensionDescriptor
 import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
 
@@ -17,15 +16,3 @@ interface IrGenerationExtension {
 
     fun generate(moduleFragment: IrModuleFragment, pluginContext: IrPluginContext)
 }
-
-// Extension point for plugins which run before any lowerings, but after the Ir has been constructed.
-@Deprecated("This is a temporary class which will be replaced with another extension mechanism soon.", level = DeprecationLevel.ERROR)
-interface PureIrGenerationExtension {
-    @Suppress("DEPRECATION_ERROR")
-    companion object :
-        ProjectExtensionDescriptor<PureIrGenerationExtension>(
-            "org.jetbrains.kotlin.pureIrGenerationExtension", PureIrGenerationExtension::class.java
-        )
-
-    fun generate(moduleFragment: IrModuleFragment, context: CommonBackendContext)
-}

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

@@ -120,11 +120,6 @@ object JvmBackendFacade {
             context.typeMapper.mapType(context.referenceClass(descriptor).defaultType)
         }
 
-        @Suppress("DEPRECATION_ERROR")
-        for (extension in org.jetbrains.kotlin.backend.common.extensions.PureIrGenerationExtension.getInstances(state.project)) {
-            extension.generate(irModuleFragment, context)
-        }
-
         JvmLower(context).lower(irModuleFragment)
 
         for (generateMultifileFacade in listOf(true, false)) {