Make Mozart view manager use the new compositor.

mojo/services/ui/views/interfaces/view_associates.mojom

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+[DartPackage="mojo_services"]
+module mojo.ui;
+
+import "mojo/public/interfaces/application/service_provider.mojom";
+import "mojo/services/ui/views/interfaces/views.mojom";
+import "mojo/services/ui/views/interfaces/view_trees.mojom";
+
+// View associates are trusted components that are attached to a view manager
+// instance with the purpose of offering additional services to views and
+// view trees registered beyond the basic operations performed by the
+// view manager itself.  Associates may be used to implement input,
+// accessibility, editing, and other capabilities.
+//
+// Associates are coupled to a view manager instance for the entire life
+// of that view manager.  Associates cannot be dynamically added or removed
+// since applications rely on the services that they offer and expect them
+// to be available for the lifetime of their views.  Moreover, all views and
+// view trees registered with a particular view manager instance share
+// the same set of associates.
+//
+// This mechanism is designed to avoid a potential explosion in complexity
+// if all features which depend on the state of views were implemented
+// in one place.
+//
+// TODO(jeffbrown): In the current implementation, the view manager binds
+// to a hard coded set of associates at start up time which can be overridden
+// from the command-line.  We should find a better way to register associates
+// once we decide how the system as a whole should be initialized.
+[ServiceName="mojo::ui::ViewAssociate"]
+interface ViewAssociate {
+  // Connects to the associate.
+  //
+  // The |inspector| provides a means for the view associate to query state
+  // from the view manager.
+  //
+  // The associate must return information about the services that it
+  // offers in |info|.
+  Connect(ViewInspector inspector) => (ViewAssociateInfo info);
+
+  // Asks the associate to provide the view service identified by
+  // |interface_name| through the message |pipe| endpoint supplied by
+  // the caller.  If the host is not willing or able to provide the requested
+  // service, it should close the |pipe|.
+  //
+  // The |view_token| is the token of the view which requested the service.
+  ConnectToViewService(ViewToken view_token, string service_name,
+      handle<message_pipe> pipe);
+
+  // Asks the associate to provide the view tree service identified by
+  // |interface_name| through the message |pipe| endpoint supplied by
+  // the caller.  If the host is not willing or able to provide the requested
+  // service, it should close the |pipe|.
+  //
+  // The |view_tree_token| is the token of the view tree which requested
+  // the service.
+  ConnectToViewTreeService(ViewTreeToken view_tree_token,
+      string service_name, handle<message_pipe> pipe);
+};
+
+// Provides information about the services offered by an associate.
+struct ViewAssociateInfo {
+  // The names of view services offered by the associate.
+  // May be null if none.
+  array<string>? view_service_names;
+
+  // The names of view tree services offered by the associate.
+  // May be null if none.
+  array<string>? view_tree_service_names;
+};
+
+// Provides a view associate with the ability to inspect and perform operations
+// on the contents of views and view trees.
+interface ViewInspector {
+
+};