Extract new method from the publicly used interface for compatibility

Note that we can't just use ``@JvmDefault` annotation as the main change
 is in the `core` module which targets Java 6

 #KT-42259 Fixed

compiler/frontend.java/src/org/jetbrains/kotlin/load/kotlin/incremental/IncrementalPackageFragmentProvider.kt

@@ -18,7 +18,7 @@ package org.jetbrains.kotlin.load.kotlin.incremental
 
 import org.jetbrains.kotlin.descriptors.ModuleDescriptor
 import org.jetbrains.kotlin.descriptors.PackageFragmentDescriptor
-import org.jetbrains.kotlin.descriptors.PackageFragmentProvider
+import org.jetbrains.kotlin.descriptors.PackageFragmentProviderOptimized
 import org.jetbrains.kotlin.descriptors.impl.PackageFragmentDescriptorImpl
 import org.jetbrains.kotlin.load.kotlin.JvmPackagePartSource
 import org.jetbrains.kotlin.load.kotlin.KotlinClassFinder
@@ -49,7 +49,7 @@ class IncrementalPackageFragmentProvider(
     val incrementalCache: IncrementalCache,
     val target: TargetId,
     private val kotlinClassFinder: KotlinClassFinder
-) : PackageFragmentProvider {
+) : PackageFragmentProviderOptimized {
     private val fqNameToPackageFragment =
         PackagePartClassUtils.getFilesWithCallables(sourceFiles)
             .mapTo(hashSetOf()) { it.packageFqName }

compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/multiplatform/OptionalAnnotationPackageFragmentProvider.kt

@@ -33,7 +33,7 @@ class OptionalAnnotationPackageFragmentProvider(
     notFoundClasses: NotFoundClasses,
     languageVersionSettings: LanguageVersionSettings,
     packagePartProvider: PackagePartProvider,
-) : PackageFragmentProvider {
+) : PackageFragmentProviderOptimized {
     val packages: Map<FqName, PackageFragmentDescriptor> by storageManager.createLazyValue p@{
         // We call getAllOptionalAnnotationClasses under lazy value only because IncrementalPackagePartProvider requires
         // deserializationConfiguration to be injected.