Get rid of 'class object' usages in code and builtins

Replace some comments and library usages as well

js/js.frontend/src/org/jetbrains/kotlin/js/PredefinedAnnotation.kt

@@ -28,7 +28,7 @@ public enum class PredefinedAnnotation(fqName: String) {
 
     public val fqName: FqName = FqName(fqName)
 
-    class object {
+    companion object {
         // TODO: replace with straight assignment when KT-5761 will be fixed
         val WITH_CUSTOM_NAME by Delegates.lazy { setOf(LIBRARY, NATIVE) }
     }

js/js.frontend/src/org/jetbrains/kotlin/js/analyzer/JsAnalysisResult.kt

@@ -28,7 +28,7 @@ public class JsAnalysisResult(
         moduleDescriptor: ModuleDescriptor
 ) : AnalysisResult(bindingTrace.getBindingContext(), moduleDescriptor) {
 
-    class object {
+    companion object {
         platformStatic public fun success(trace: BindingTrace, module: ModuleDescriptor): JsAnalysisResult {
             return JsAnalysisResult(trace, module)
         }

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

@@ -54,7 +54,7 @@ import org.jetbrains.kotlin.resolve.TemporaryBindingTrace
 
 public class JsCallChecker : CallChecker {
 
-    class object {
+    companion object {
         private val JS_PATTERN: DescriptorPredicate = PatternBuilder.pattern("kotlin.js.js(String)")
 
         platformStatic