Don't add script files to facade indices

#KT-12445 Fixed

idea/tests/org/jetbrains/kotlin/asJava/KtFileLightClassTest.kt

@@ -16,10 +16,12 @@
 
 package org.jetbrains.kotlin.asJava
 
+import com.intellij.psi.search.GlobalSearchScope
 import com.intellij.testFramework.LightProjectDescriptor
 import org.jetbrains.kotlin.idea.test.KotlinLightCodeInsightFixtureTestCase
 import org.jetbrains.kotlin.idea.test.KotlinLightProjectDescriptor
 import org.jetbrains.kotlin.idea.test.PluginTestCaseBase
+import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.psi.KtFile
 
 class KtFileLightClassTest : KotlinLightCodeInsightFixtureTestCase() {
@@ -53,6 +55,13 @@ class KtFileLightClassTest : KotlinLightCodeInsightFixtureTestCase() {
         assertEquals(0, aClass.getMethods().size)
     }
 
+    fun testNoFacadeForScript() {
+        val file = myFixture.configureByText("foo.kts", "package foo") as KtFile
+        assertEquals(0, file.classes.size)
+        val facadeFiles = LightClassGenerationSupport.getInstance(project).findFilesForFacade(FqName("foo.FooKt"), GlobalSearchScope.allScope(project))
+        assertEquals(0, facadeFiles.size)
+    }
+
     override fun getTestDataPath(): String? {
         return PluginTestCaseBase.getTestDataPathBase() + "/asJava/fileLightClass/"
     }