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

Replace some comments and library usages as well

core/descriptors.runtime/src/org/jetbrains/kotlin/load/java/structure/reflect/ReflectJavaAnnotationArguments.kt

@@ -22,7 +22,7 @@ import org.jetbrains.kotlin.name.Name
 abstract class ReflectJavaAnnotationArgument(
         override val name: Name?
 ) : JavaAnnotationArgument {
-    class object Factory {
+    companion object Factory {
         fun create(value: Any, name: Name?): ReflectJavaAnnotationArgument {
             return when {
                 value.javaClass.isEnumClassOrSpecializedEnumEntryClass() -> ReflectJavaEnumValueAnnotationArgument(name, value as Enum<*>)

core/descriptors.runtime/src/org/jetbrains/kotlin/load/java/structure/reflect/ReflectJavaType.kt

@@ -27,7 +27,7 @@ public abstract class ReflectJavaType : JavaType {
 
     override fun createArrayType(): JavaArrayType = throw UnsupportedOperationException()
 
-    class object Factory {
+    companion object Factory {
         fun create(type: Type): ReflectJavaType {
             return when {
                 type is Class<*> && type.isPrimitive() -> ReflectJavaPrimitiveType(type)

core/descriptors.runtime/src/org/jetbrains/kotlin/load/kotlin/reflect/ReflectKotlinClass.kt

@@ -44,7 +44,7 @@ public class ReflectKotlinClass private(
         private val classHeader: KotlinClassHeader
 ) : KotlinJvmBinaryClass {
 
-    class object Factory {
+    companion object Factory {
 
         public fun create(klass: Class<*>): ReflectKotlinClass? {
             val headerReader = ReadKotlinClassHeaderAnnotationVisitor()

core/descriptors.runtime/src/org/jetbrains/kotlin/load/kotlin/reflect/RuntimeModuleData.kt

@@ -29,7 +29,7 @@ public class RuntimeModuleData private(private val injector: InjectorForRuntimeD
 
     public val localClassResolver: LocalClassResolver get() = injector.getDeserializationComponentsForJava().components.localClassResolver
 
-    class object {
+    companion object {
         public fun create(classLoader: ClassLoader): RuntimeModuleData {
             val module = ModuleDescriptorImpl(Name.special("<runtime module for $classLoader>"), listOf(), JavaToKotlinClassMap.INSTANCE)
             module.addDependencyOnModule(module)