[FIR IDE] HL API Better support of nullability and modality

idea/idea-frontend-api/src/org/jetbrains/kotlin/idea/frontend/api/symbols/KtPropertyAccessorSymbol.kt

@@ -14,6 +14,7 @@ sealed class KtPropertyAccessorSymbol : KtCallableSymbol(),
     abstract val isDefault: Boolean
     abstract val isInline: Boolean
     abstract val isOverride: Boolean
+    abstract val hasBody: Boolean
 
     abstract val symbolKind: KtSymbolKind
 

idea/idea-frontend-api/src/org/jetbrains/kotlin/idea/frontend/api/symbols/KtVariableLikeSymbol.kt

@@ -53,6 +53,8 @@ abstract class KtPropertySymbol : KtVariableSymbol(),
 
     abstract val hasBackingField: Boolean
 
+    abstract val isLateInit: Boolean
+
     abstract val isConst: Boolean
 
     abstract val isOverride: Boolean