Support bridges in interfaces. Fix for KT-12416: Missed bridges in js backend

#KT-12416 Fixed

js/js.translator/src/org/jetbrains/kotlin/js/translate/declaration/ClassTranslator.kt

@@ -77,6 +77,8 @@ class ClassTranslator private constructor(
 
     private fun isTrait(): Boolean = descriptor.kind == ClassKind.INTERFACE
 
+    private fun isAnnotation(): Boolean = descriptor.kind == ClassKind.ANNOTATION_CLASS
+
     private fun generateClassCreateInvocationArguments() {
         val properties = SmartList<JsPropertyInitializer>()
         val staticProperties = SmartList<JsPropertyInitializer>()
@@ -369,7 +371,7 @@ class ClassTranslator private constructor(
     }
 
     private fun generatedBridgeMethods(properties: MutableList<JsPropertyInitializer>) {
-        if (isTrait()) return
+        if (isAnnotation()) return
 
         generateBridgesToTraitImpl(properties)
 
@@ -387,7 +389,10 @@ class ClassTranslator private constructor(
     private fun generateOtherBridges(properties: MutableList<JsPropertyInitializer>) {
         for (memberDescriptor in descriptor.defaultType.memberScope.getContributedDescriptors()) {
             if (memberDescriptor is FunctionDescriptor) {
-                val bridgesToGenerate = generateBridgesForFunctionDescriptor(memberDescriptor, identity())
+                val bridgesToGenerate = generateBridgesForFunctionDescriptor(memberDescriptor, identity()) {
+                    //There is no DefaultImpls in js backend so if method non-abstract it should be recognized as non-abstract on bridges calculation
+                    false
+                }
 
                 for (bridge in bridgesToGenerate) {
                     generateBridge(bridge, properties)