chore(typings): mark underscore methods @internal.

This allows TypeScript to produce an API surface which matches the Dart semantics.
I found these with:
gulp build.js.dev && find dist/js/dev/es5/angular2/src -name "*.d.ts" -exec grep -H -n '^ *_' {} \;

Closes #4638

modules/angular2/src/core/linker/component_url_mapper.ts

@@ -24,6 +24,7 @@ export class ComponentUrlMapper {
 }
 
 export class RuntimeComponentUrlMapper extends ComponentUrlMapper {
+  /** @internal */
   _componentUrls = new Map<Type, string>();
 
   constructor() { super(); }

modules/angular2/src/core/linker/element_injector.ts

@@ -78,6 +78,7 @@ export class StaticKeys {
 }
 
 export class TreeNode<T extends TreeNode<any>> {
+  /** @internal */
   _parent: T;
   constructor(parent: T) {
     if (isPresent(parent)) {
@@ -102,6 +103,7 @@ export class DirectiveDependency extends Dependency {
     this._verify();
   }
 
+  /** @internal */
   _verify(): void {
     var count = 0;
     if (isPresent(this.queryDecorator)) count++;
@@ -288,12 +290,15 @@ export class ProtoElementInjector {
     resolvedViewBindings.forEach(b => bd.push(new BindingWithVisibility(b, Visibility.Private)));
   }
 
+  /** @internal */
+  public _firstBindingIsComponent: boolean;
 
 
   constructor(public parent: ProtoElementInjector, public index: number,
               bwv: BindingWithVisibility[], public distanceToParent: number,
-              public _firstBindingIsComponent: boolean,
+              _firstBindingIsComponent: boolean,
               public directiveVariableBindings: Map<string, number>) {
+    this._firstBindingIsComponent = _firstBindingIsComponent;
     var length = bwv.length;
     this.protoInjector = new ProtoInjector(bwv);
     this.eventEmitterAccessors = ListWrapper.createFixedSize(length);
@@ -327,10 +332,12 @@ export class ElementInjector extends TreeNode<ElementInjector> implements Depend
 
   private _injector: Injector;
   private _strategy: _ElementInjectorStrategy;
+  /** @internal */
+  public _proto: ProtoElementInjector;
 
-  constructor(public _proto: ProtoElementInjector, parent: ElementInjector) {
+  constructor(_proto: ProtoElementInjector, parent: ElementInjector) {
     super(parent);
-
+    this._proto = _proto;
     this._injector =
         new Injector(this._proto.protoInjector, null, this, () => this._debugContext());
 

modules/angular2/src/core/linker/view_manager.ts

@@ -219,6 +219,7 @@ export class AppViewManager_ extends AppViewManager {
     return this._utils.getComponentInstance(hostView, boundElementIndex);
   }
 
+  /** @internal */
   _createRootHostViewScope: WtfScopeFn = wtfCreateScope('AppViewManager#createRootHostView()');
 
   createRootHostView(hostProtoViewRef: ProtoViewRef, overrideSelector: string,
@@ -239,6 +240,7 @@ export class AppViewManager_ extends AppViewManager {
     return wtfLeave(s, hostView.ref);
   }
 
+  /** @internal */
   _destroyRootHostViewScope: WtfScopeFn = wtfCreateScope('AppViewManager#destroyRootHostView()');
 
   destroyRootHostView(hostViewRef: HostViewRef) {
@@ -254,6 +256,7 @@ export class AppViewManager_ extends AppViewManager {
     wtfLeave(s);
   }
 
+  /** @internal */
   _createEmbeddedViewInContainerScope: WtfScopeFn =
       wtfCreateScope('AppViewManager#createEmbeddedViewInContainer()');
 
@@ -269,6 +272,7 @@ export class AppViewManager_ extends AppViewManager {
                                                    templateRef.elementRef, null));
   }
 
+  /** @internal */
   _createHostViewInContainerScope: WtfScopeFn =
       wtfCreateScope('AppViewManager#createHostViewInContainer()');
 
@@ -289,6 +293,7 @@ export class AppViewManager_ extends AppViewManager {
   /**
    *
    * See {@link AppViewManager#destroyViewInContainer}.
+   * @internal
    */
   _createViewInContainer(viewContainerLocation: ElementRef, index: number,
                          protoView: viewModule.AppProtoView, context: ElementRef,
@@ -320,6 +325,7 @@ export class AppViewManager_ extends AppViewManager {
     return view.ref;
   }
 
+  /** @internal */
   _attachRenderView(parentView: viewModule.AppView, boundElementIndex: number, index: number,
                     view: viewModule.AppView) {
     var elementRef = parentView.elementRefs[boundElementIndex];
@@ -331,6 +337,7 @@ export class AppViewManager_ extends AppViewManager {
     }
   }
 
+  /** @internal */
   _destroyViewInContainerScope = wtfCreateScope('AppViewMananger#destroyViewInContainer()');
 
   destroyViewInContainer(viewContainerLocation: ElementRef, index: number) {
@@ -341,6 +348,7 @@ export class AppViewManager_ extends AppViewManager {
     wtfLeave(s);
   }
 
+  /** @internal */
   _attachViewInContainerScope = wtfCreateScope('AppViewMananger#attachViewInContainer()');
 
   // TODO(i): refactor detachViewInContainer+attachViewInContainer to moveViewInContainer
@@ -361,6 +369,7 @@ export class AppViewManager_ extends AppViewManager {
     return wtfLeave(s, viewRef);
   }
 
+  /** @internal */
   _detachViewInContainerScope = wtfCreateScope('AppViewMananger#detachViewInContainer()');
 
   // TODO(i): refactor detachViewInContainer+attachViewInContainer to moveViewInContainer
@@ -375,6 +384,7 @@ export class AppViewManager_ extends AppViewManager {
     return wtfLeave(s, view.ref);
   }
 
+  /** @internal */
   _createMainView(protoView: viewModule.AppProtoView,
                   renderViewWithFragments: RenderViewWithFragments): viewModule.AppView {
     var mergedParentView =
@@ -384,6 +394,7 @@ export class AppViewManager_ extends AppViewManager {
     return mergedParentView;
   }
 
+  /** @internal */
   _createPooledView(protoView: viewModule.AppProtoView): viewModule.AppView {
     var view = this._viewPool.getView(protoView);
     if (isBlank(view)) {
@@ -394,6 +405,7 @@ export class AppViewManager_ extends AppViewManager {
     return view;
   }
 
+  /** @internal */
   _destroyPooledView(view: viewModule.AppView) {
     var wasReturned = this._viewPool.returnView(view);
     if (!wasReturned) {
@@ -402,6 +414,7 @@ export class AppViewManager_ extends AppViewManager {
     }
   }
 
+  /** @internal */
   _destroyViewInContainer(parentView: viewModule.AppView, boundElementIndex: number,
                           index: number) {
     var viewContainer = parentView.viewContainers[boundElementIndex];
@@ -422,6 +435,7 @@ export class AppViewManager_ extends AppViewManager {
     }
   }
 
+  /** @internal */
   _viewDehydrateRecurse(view: viewModule.AppView) {
     if (view.hydrated()) {
       this._utils.dehydrateView(view);

modules/angular2/src/core/linker/view_manager_utils.ts

@@ -172,6 +172,7 @@ export class AppViewManagerUtils {
                       contextView.locals);
   }
 
+  /** @internal */
   _hydrateView(initView: viewModule.AppView, imperativelyCreatedInjector: Injector,
                hostElementInjector: eli.ElementInjector, context: Object, parentLocals: Locals) {
     var viewIdx = initView.viewOffset;
@@ -213,6 +214,7 @@ export class AppViewManagerUtils {
     }
   }
 
+  /** @internal */
   _populateViewLocals(view: viewModule.AppView, elementInjector: eli.ElementInjector,
                       boundElementIdx: number): void {
     if (isPresent(elementInjector.getDirectiveVariableBindings())) {
@@ -226,6 +228,7 @@ export class AppViewManagerUtils {
     }
   }
 
+  /** @internal */
   _setUpEventEmitters(view: viewModule.AppView, elementInjector: eli.ElementInjector,
                       boundElementIndex: number) {
     var emitters = elementInjector.getEventEmitterAccessors();

modules/angular2/src/core/linker/view_pool.ts

@@ -9,7 +9,9 @@ export const APP_VIEW_POOL_CAPACITY = CONST_EXPR(new OpaqueToken('AppViewPool.vi
 
 @Injectable()
 export class AppViewPool {
+  /** @internal */
   _poolCapacityPerProtoView: number;
+  /** @internal */
   _pooledViewsPerProtoView = new Map<viewModule.AppProtoView, Array<viewModule.AppView>>();
 
   constructor(@Inject(APP_VIEW_POOL_CAPACITY) poolCapacityPerProtoView) {

modules/angular2/src/core/linker/view_ref.ts

@@ -98,8 +98,12 @@ export abstract class ViewRef implements HostViewRef {
 
 export class ViewRef_ extends ViewRef {
   private _changeDetectorRef: ChangeDetectorRef = null;
-
-  constructor(public _view: viewModule.AppView) { super(); }
+  /** @internal */
+  public _view: viewModule.AppView;
+  constructor(_view: viewModule.AppView) {
+    super();
+    this._view = _view;
+  }
 
   /**
    * Return `RenderViewRef`
@@ -166,5 +170,10 @@ export class ViewRef_ extends ViewRef {
 export abstract class ProtoViewRef {}
 
 export class ProtoViewRef_ extends ProtoViewRef {
-  constructor(public _protoView: viewModule.AppProtoView) { super(); }
+  /** @internal */
+  public _protoView: viewModule.AppProtoView;
+  constructor(_protoView: viewModule.AppProtoView) {
+    super();
+    this._protoView = _protoView;
+  }
 }

modules/angular2/src/core/linker/view_resolver.ts

@@ -11,6 +11,7 @@ import {reflector} from 'angular2/src/core/reflection/reflection';
 
 @Injectable()
 export class ViewResolver {
+  /** @internal */
   _cache = new Map<Type, ViewMetadata>();
 
   resolve(component: Type): ViewMetadata {
@@ -24,6 +25,7 @@ export class ViewResolver {
     return view;
   }
 
+  /** @internal */
   _resolve(component: Type): ViewMetadata {
     var compMeta: ComponentMetadata;
     var viewMeta: ViewMetadata;
@@ -87,6 +89,7 @@ export class ViewResolver {
     return null;
   }
 
+  /** @internal */
   _throwMixingViewAndComponent(propertyName: string, component: Type): void {
     throw new BaseException(
         `Component '${stringify(component)}' cannot have both '${propertyName}' and '@View' set at the same time"`);