[JS FE] Prohibit external inline classes

#KT-26138 Fixed

compiler/testData/diagnostics/testsWithJsStdLib/native/inlineClass.kt

@@ -0,0 +1,9 @@
+// !LANGUAGE: +InlineClasses
+
+external inline class <!WRONG_EXTERNAL_DECLARATION!>C(<!EXTERNAL_CLASS_CONSTRUCTOR_PROPERTY_PARAMETER!>val a: Int<!>)<!> {
+    fun foo()
+}
+
+<!WRONG_MODIFIER_TARGET!>inline<!> external enum class <!WRONG_EXTERNAL_DECLARATION!>E<!> {
+    A
+}

compiler/testData/diagnostics/testsWithJsStdLib/native/inlineClass.txt

@@ -0,0 +1,27 @@
+package
+
+public final external inline class C {
+    public constructor C(/*0*/ a: kotlin.Int)
+    public final val a: kotlin.Int
+    public open override /*1*/ /*synthesized*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final fun foo(): kotlin.Unit
+    public open override /*1*/ /*synthesized*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*synthesized*/ fun toString(): kotlin.String
+}
+
+public final external inline enum class E : kotlin.Enum<E> {
+    enum entry A
+
+    private constructor E()
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: E): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*synthesized*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): E
+    public final /*synthesized*/ fun values(): kotlin.Array<E>
+}

compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestWithJsStdLibGenerated.java

@@ -659,6 +659,11 @@ public class DiagnosticsTestWithJsStdLibGenerated extends AbstractDiagnosticsTes
             runTest("compiler/testData/diagnostics/testsWithJsStdLib/native/inline.kt");
         }
 
+        @TestMetadata("inlineClass.kt")
+        public void testInlineClass() throws Exception {
+            runTest("compiler/testData/diagnostics/testsWithJsStdLib/native/inlineClass.kt");
+        }
+
         @TestMetadata("inlineExtensionToNative.kt")
         public void testInlineExtensionToNative() throws Exception {
             runTest("compiler/testData/diagnostics/testsWithJsStdLib/native/inlineExtensionToNative.kt");

js/js.frontend/src/org/jetbrains/kotlin/js/resolve/diagnostics/JsExternalChecker.kt

@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
  */
 
 package org.jetbrains.kotlin.js.resolve.diagnostics
@@ -28,8 +17,8 @@ import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.resolve.calls.callUtil.getResolvedCall
-import org.jetbrains.kotlin.resolve.checkers.DeclarationCheckerContext
 import org.jetbrains.kotlin.resolve.checkers.DeclarationChecker
+import org.jetbrains.kotlin.resolve.checkers.DeclarationCheckerContext
 import org.jetbrains.kotlin.resolve.descriptorUtil.*
 import org.jetbrains.kotlin.resolve.source.getPsi
 import org.jetbrains.kotlin.types.TypeUtils
@@ -59,6 +48,9 @@ object JsExternalChecker : DeclarationChecker {
         else if (descriptor is ClassDescriptor && descriptor.isInner) {
             trace.report(ErrorsJs.WRONG_EXTERNAL_DECLARATION.on(declaration, "inner class"))
         }
+        else if (descriptor is ClassDescriptor && descriptor.isInline) {
+            trace.report(ErrorsJs.WRONG_EXTERNAL_DECLARATION.on(declaration, "inline class"))
+        }
         else if (isPrivateMemberOfExternalClass(descriptor)) {
             trace.report(ErrorsJs.WRONG_EXTERNAL_DECLARATION.on(declaration, "private member of class"))
         }