[FIR] Make check for dangling modifier lists use stubs

Seventh step for ^KT-52615

Merge-request: KT-MR-8651
Merged-by: Egor Kulikov <Egor.Kulikov@jetbrains.com>

compiler/psi/src/org/jetbrains/kotlin/psi/KtClassBody.kt

@@ -69,5 +69,11 @@ class KtClassBody : KtElementImplStub<KotlinPlaceHolderStub<KtClassBody>>, KtDec
      * @return annotations that do not belong to any declaration due to incomplete code or syntax errors
      */
     val danglingAnnotations: List<KtAnnotationEntry>
-        get() = getStubOrPsiChildrenAsList(MODIFIER_LIST).flatMap { it.annotationEntries }
+        get() = danglingModifierLists.flatMap { it.annotationEntries }
+
+    /**
+     * @return modifier lists that do not belong to any declaration due to incomplete code or syntax errors
+     */
+    val danglingModifierLists: List<KtModifierList>
+        get() = getStubOrPsiChildrenAsList(MODIFIER_LIST)
 }

compiler/psi/src/org/jetbrains/kotlin/psi/KtFile.kt

@@ -128,18 +128,23 @@ open class KtFile(viewProvider: FileViewProvider, val isCompiled: Boolean) :
         get() = script != null
 
     /**
-     * @return annotations that do not belong to any declaration due to incomplete code or syntax errors
+     * @return modifier lists that do not belong to any declaration due to incomplete code or syntax errors
      */
-    val danglingAnnotations: List<KtAnnotationEntry>
+    val danglingModifierLists: Array<out KtModifierList>
         get() {
             val stub = stub
-            val danglingModifierLists = stub?.getChildrenByType(
+            return stub?.getChildrenByType(
                 KtStubElementTypes.MODIFIER_LIST,
                 KtStubElementTypes.MODIFIER_LIST.arrayFactory
             ) ?: findChildrenByClass(KtModifierList::class.java)
-            return danglingModifierLists.flatMap { obj: KtModifierList -> obj.annotationEntries }
         }
 
+    /**
+     * @return annotations that do not belong to any declaration due to incomplete code or syntax errors
+     */
+    val danglingAnnotations: List<KtAnnotationEntry>
+        get() = danglingModifierLists.flatMap { obj: KtModifierList -> obj.annotationEntries }
+
     override fun getFileType(): FileType = KotlinFileType.INSTANCE
 
     override fun toString(): String = "KtFile: $name"