Do not report "reflection is not available" on built-in sources

compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/checkers/ReflectionAPICallChecker.kt

@@ -17,10 +17,13 @@
 package org.jetbrains.kotlin.resolve.jvm.checkers
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.builtins.KOTLIN_REFLECT_FQ_NAME
+import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.builtins.ReflectionTypes
 import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.descriptors.ModuleDescriptor
 import org.jetbrains.kotlin.load.java.JvmAbi
+import org.jetbrains.kotlin.psi.KtFile
 import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.resolve.calls.checkers.CallChecker
 import org.jetbrains.kotlin.resolve.calls.checkers.CallCheckerContext
@@ -48,6 +51,9 @@ class ReflectionAPICallChecker(private val module: ModuleDescriptor, storageMana
     override fun check(resolvedCall: ResolvedCall<*>, reportOn: PsiElement, context: CallCheckerContext) {
         if (isReflectionAvailable) return
 
+        // Do not report the diagnostic on built-in sources
+        if (isReflectionSource(reportOn)) return
+
         val descriptor = resolvedCall.resultingDescriptor
         val containingClass = descriptor.containingDeclaration as? ClassDescriptor ?: return
         if (!ReflectionTypes.isReflectionClass(containingClass)) return
@@ -66,4 +72,11 @@ class ReflectionAPICallChecker(private val module: ModuleDescriptor, storageMana
 
         context.trace.report(NO_REFLECTION_IN_CLASS_PATH.on(reportOn))
     }
+
+    private fun isReflectionSource(reportOn: PsiElement): Boolean {
+        val file = reportOn.containingFile as? KtFile ?: return false
+        val fqName = file.packageFqName.toUnsafe()
+        return fqName.startsWith(KotlinBuiltIns.BUILT_INS_PACKAGE_NAME) &&
+               (fqName == KOTLIN_REFLECT_FQ_NAME.toUnsafe() || fqName.asString().startsWith(KOTLIN_REFLECT_FQ_NAME.asString() + "."))
+    }
 }