Sort by class name in navigation bar (KT-10215)

#KT-10215 Fixed

idea/resources/META-INF/plugin-common.xml

@@ -3425,5 +3425,7 @@
     <postStartupActivity implementation="org.jetbrains.kotlin.idea.framework.TargetRetrieveActivity"/>
 
     <stripTrailingSpacesFilterFactory implementation="org.jetbrains.kotlin.idea.editor.KotlinStripTrailingSpacesFilterFactory"/>
+
+    <navbar implementation="org.jetbrains.kotlin.idea.navigationToolbar.KotlinNavBarModelExtension"/>
   </extensions>
 </idea-plugin>

idea/src/org/jetbrains/kotlin/idea/navigationToolbar/KotlinNavBarModelExtension.kt

@@ -0,0 +1,24 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.idea.navigationToolbar
+
+import com.intellij.ide.navigationToolbar.AbstractNavBarModelExtension
+import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.asJava.toLightClass
+import org.jetbrains.kotlin.idea.KotlinIconProvider
+import org.jetbrains.kotlin.psi.KtFile
+
+class KotlinNavBarModelExtension : AbstractNavBarModelExtension() {
+    override fun getPresentableText(`object`: Any?): String? {
+        return null
+    }
+
+    override fun adjustElement(psiElement: PsiElement?): PsiElement? {
+        val containingFile = psiElement?.containingFile as? KtFile ?: return psiElement
+        if (containingFile.isScript()) return psiElement
+        return KotlinIconProvider.getSingleClass(containingFile)?.toLightClass() ?: psiElement
+    }
+}