[Contextual Search] Add Mojo-enabled API component.

components/contextual_search/renderer/overlay_js_render_frame_observer.cc

+// 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.
+
+#include "components/contextual_search/renderer/overlay_js_render_frame_observer.h"
+
+#include "base/bind.h"
+#include "components/contextual_search/renderer/contextual_search_wrapper.h"
+#include "components/contextual_search/renderer/overlay_page_notifier_service_impl.h"
+#include "content/public/common/service_registry.h"
+#include "content/public/renderer/render_frame.h"
+#include "v8/include/v8.h"
+
+namespace contextual_search {
+
+OverlayJsRenderFrameObserver::OverlayJsRenderFrameObserver(
+    content::RenderFrame* render_frame)
+    : RenderFrameObserver(render_frame),
+      is_contextual_search_overlay_(false),
+      weak_factory_(this) {}
+
+OverlayJsRenderFrameObserver::~OverlayJsRenderFrameObserver() {}
+
+void OverlayJsRenderFrameObserver::DidStartProvisionalLoad() {
+  RegisterMojoService();
+}
+
+void OverlayJsRenderFrameObserver::RegisterMojoService() {
+  render_frame()->GetServiceRegistry()->AddService(base::Bind(
+      &OverlayJsRenderFrameObserver::CreateOverlayPageNotifierService,
+      weak_factory_.GetWeakPtr()));
+}
+
+void OverlayJsRenderFrameObserver::CreateOverlayPageNotifierService(
+    mojo::InterfaceRequest<OverlayPageNotifierService> request) {
+  // This is strongly bound to and owned by the pipe.
+  new OverlayPageNotifierServiceImpl(this, request.Pass());
+}
+
+void OverlayJsRenderFrameObserver::SetIsContextualSearchOverlay() {
+  is_contextual_search_overlay_ = true;
+}
+
+void OverlayJsRenderFrameObserver::DidClearWindowObject() {
+  if (is_contextual_search_overlay_) {
+    contextual_search::ContextualSearchWrapper::Install(render_frame());
+  }
+}
+
+void OverlayJsRenderFrameObserver::DidFinishLoad() {
+  // If no message about the Contextual Search overlay was received at this
+  // point, there will not be one; remove the OverlayPageNotifierService
+  // from the registry.
+  render_frame()
+      ->GetServiceRegistry()
+      ->RemoveService<OverlayPageNotifierService>();
+}
+
+}  // namespace contextual_search