Change MojoWebUIController to use mojo::StrongBindingSet.

chrome/browser/ui/webui/engagement/site_engagement_ui_handler.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 "chrome/browser/ui/webui/engagement/site_engagement_ui_handler.h"
+
+#include <utility>
+
+#include "chrome/browser/engagement/site_engagement_service.h"
+#include "chrome/browser/profiles/profile.h"
+#include "mojo/common/url_type_converters.h"
+
+// Implementation of SiteEngagementUIHandler that gets information from the
+// SiteEngagementService to provide data for the WebUI.
+SiteEngagementUIHandlerImpl::SiteEngagementUIHandlerImpl(content::WebUI* web_ui)
+    : profile_(Profile::FromWebUI(web_ui)) {
+  DCHECK(profile_);
+}
+
+SiteEngagementUIHandlerImpl::~SiteEngagementUIHandlerImpl() {}
+
+// SiteEngagementUIHandler overrides:
+void SiteEngagementUIHandlerImpl::GetSiteEngagementInfo(
+    const GetSiteEngagementInfoCallback& callback) {
+  mojo::Array<SiteEngagementInfoPtr> engagement_info(0);
+
+  SiteEngagementService* service = SiteEngagementService::Get(profile_);
+
+  for (const std::pair<GURL, double>& info : service->GetScoreMap()) {
+    SiteEngagementInfoPtr origin_info(SiteEngagementInfo::New());
+    origin_info->origin = mojo::String::From(info.first);
+    origin_info->score = info.second;
+    engagement_info.push_back(std::move(origin_info));
+  }
+
+  callback.Run(std::move(engagement_info));
+}