Show enum constants in Goto Symbol

#KT-6535 Fixed

idea/src/org/jetbrains/kotlin/idea/goto/gotoContributors.kt

@@ -20,8 +20,6 @@ import com.intellij.navigation.ChooseByNameContributor
 import com.intellij.navigation.GotoClassContributor
 import com.intellij.navigation.NavigationItem
 import com.intellij.openapi.project.Project
-import com.intellij.openapi.vfs.VirtualFile
-import com.intellij.psi.search.DelegatingGlobalSearchScope
 import com.intellij.psi.search.GlobalSearchScope
 import com.intellij.psi.stubs.StubIndex
 import org.jetbrains.kotlin.asJava.LightClassUtil
@@ -88,15 +86,11 @@ class KotlinGotoSymbolContributor : ChooseByNameContributor {
             LightClassUtil.getLightClassBackingField(it) == null ||
             it.containingClass()?.isInterface() ?: false
         }
-        result += KotlinClassShortNameIndex.getInstance().get(name, project, BuiltInClassesScope(noLibrarySourceScope))
+        result += KotlinClassShortNameIndex.getInstance().get(name, project, noLibrarySourceScope).filter {
+            it is KtEnumEntry || it.containingFile.virtualFile?.fileType == KotlinBuiltInFileType
+        }
         result += KotlinTypeAliasShortNameIndex.getInstance().get(name, project, noLibrarySourceScope)
 
         return result.toTypedArray()
     }
 }
-
-private class BuiltInClassesScope(baseScope: GlobalSearchScope) : DelegatingGlobalSearchScope(baseScope) {
-    override fun contains(file: VirtualFile): Boolean {
-        return file.fileType == KotlinBuiltInFileType && file in myBaseScope
-    }
-}

idea/testData/navigation/gotoSymbol/enumConstants.kt

@@ -0,0 +1,5 @@
+enum class Foo { BAR, BAZ }
+
+// SEARCH_TEXT: B
+// REF: (in Foo).BAR
+// REF: (in Foo).BAZ

idea/tests/org/jetbrains/kotlin/idea/navigation/KotlinGotoTestGenerated.java

@@ -125,6 +125,12 @@ public class KotlinGotoTestGenerated extends AbstractKotlinGotoTest {
             doSymbolTest(fileName);
         }
 
+        @TestMetadata("enumConstants.kt")
+        public void testEnumConstants() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/navigation/gotoSymbol/enumConstants.kt");
+            doSymbolTest(fileName);
+        }
+
         @TestMetadata("functions.kt")
         public void testFunctions() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/testData/navigation/gotoSymbol/functions.kt");