Here is a list of all files with brief descriptions:

AppCore
layout
Anchor.h
Builder.h	Declarative functions for constructing layout trees
Callback.h
Container.h
DividerStyle.h
Foreground.h
LayoutNode.h
Length.h
Options.h
Panel.h
App.h
AppCore.h
Defines.h
Dialogs.h	Native modal message boxes for alerts and confirmations
GPUMemoryStats.h
Layout.h	Panels and containers for arranging web views across a window
Monitor.h
Platform.h	Stock platform handlers for applications that manage their own renderer
Window.h
JavaScriptCore
JavaScript.h
JSBase.h
JSContextRef.h
JSObjectRef.h
JSObjectRefPrivate.h
JSRetainPtr.h
JSStringRef.h
JSTypedArray.h
JSValueRef.h
WebKitAvailability.h
Ultralight
detail
Reflection.h
dom
data
ActionInfo.h
Binding.h
Context.h
Holders.h
Model.h
Schema.h	Factories and tags for defining a type's data-binding schema
TypeTraits.h
Value.h
ValueTraits.h
ComputedStyle.h
CSSPropertyName.h
Document.h
DocumentFragment.h
DOMRect.h
Element.h
ElementList.h
Error.h
Event.h
EventListener.h
Holders.h
JSInterop.h	Conversion functions and type traits connecting the DOM and JavaScript APIs
Node.h
NodeList.h
Range.h
Selection.h
StyleValue.h
Triggers.h
Window.h
js
API.h
Buffer.h
CallInfo.h
Class.h
Context.h
Error.h
Holder.h
Resolver.h
Task.h
TypeTraits.h
Value.h
WeakValue.h
platform
AudioOutput.h
Clipboard.h
Config.h
FileSystem.h
FontLoader.h
GPUDriver.h
Logger.h
Platform.h
Profiler.h
Surface.h
Thread.h
Bitmap.h
Buffer.h
ClipboardData.h
Color.h
Config.h
ConsoleMessage.h
Defines.h
DiagnosticsLevel.h
DOM.h
Editor.h
Exports.h
GamepadEvent.h
GCListener.h
Geometry.h
HolderTraits.h
ImageSource.h
JavaScript.h
JS.h
JSON.h
KeyCodes.h
KeyEvent.h
Listener.h
Lock.h
Matrix.h
MouseEvent.h
NetworkRequest.h
OriginRules.h
RefPtr.h
Renderer.h
RenderTarget.h
ScrollEvent.h
Session.h
String.h
String16.h
String32.h
String8.h
StringSTL.h	STL compatibility header for ultralight::String
Ultralight.h
URL.h
Vector.h
View.h