Use information from stub for contracts presence

compiler/frontend/src/org/jetbrains/kotlin/resolve/FunctionDescriptorResolver.kt

@@ -255,17 +255,17 @@ class FunctionDescriptorResolver(
         dataFlowInfo: DataFlowInfo,
         function: KtFunction
     ): LazyContractProvider? {
-        val provideByDeferredForceResolve = LazyContractProvider {
+        if (function !is KtNamedFunction) return null
-            expressionTypingServices.getBodyExpressionType(trace, scope, dataFlowInfo, function, functionDescriptor)
-        }
 
         val isContractsEnabled = languageVersionSettings.supportsFeature(LanguageFeature.AllowContractsForCustomFunctions) ||
                 // We need to enable contracts if we're compiling "kotlin"-package to be able to ship contracts in stdlib in 1.2
                 languageVersionSettings.getFlag(AnalysisFlags.allowKotlinPackage)
 
-        if (!isContractsEnabled || !function.isContractPresentPsiCheck()) return null
+        if (!isContractsEnabled || !function.mayHaveContract()) return null
 
-        return provideByDeferredForceResolve
+        return LazyContractProvider {
+            expressionTypingServices.getBodyExpressionType(trace, scope, dataFlowInfo, function, functionDescriptor)
+        }
     }
 
     private fun createValueParameterDescriptors(

compiler/psi/src/org/jetbrains/kotlin/psi/psiUtil/ktPsiUtil.kt

@@ -293,11 +293,11 @@ inline fun <reified T : KtElement, R> flatMapDescendantsOfTypeVisitor(
 
 // ----------- Contracts -------------------------------------------------------------------------------------------------------------------
 
-fun KtElement.isContractPresentPsiCheck(): Boolean {
+fun KtNamedFunction.isContractPresentPsiCheck(): Boolean {
-    val contractAllowedHere = this is KtNamedFunction &&
+    val contractAllowedHere =
-            isTopLevel &&
+        isTopLevel &&
-            hasBlockBody() &&
+        hasBlockBody() &&
-            !hasModifier(KtTokens.OPERATOR_KEYWORD)
+        !hasModifier(KtTokens.OPERATOR_KEYWORD)
     if (!contractAllowedHere) return false
 
     val firstExpression = ((this as? KtFunction)?.bodyExpression as? KtBlockExpression)?.statements?.firstOrNull() ?: return false