Implement basic mojo Permission service and use it for Geolocation.

content/browser/permissions/permission_service_context.cc

+// Copyright 2014 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 "content/browser/permissions/permission_service_context.h"
+
+#include "content/browser/permissions/permission_service_impl.h"
+#include "content/public/browser/navigation_details.h"
+#include "content/public/browser/render_frame_host.h"
+#include "content/public/browser/web_contents.h"
+
+namespace content {
+
+PermissionServiceContext::PermissionServiceContext(
+    RenderFrameHost* render_frame_host)
+    : WebContentsObserver(WebContents::FromRenderFrameHost(render_frame_host))
+    , render_frame_host_(render_frame_host)
+    , service_(nullptr) {
+}
+
+PermissionServiceContext::~PermissionServiceContext() {
+}
+
+void PermissionServiceContext::RenderFrameDeleted(
+    RenderFrameHost* render_frame_host) {
+  if (render_frame_host != render_frame_host_)
+    return;
+
+  if (service_)
+    service_->CancelPendingRequests();
+}
+
+void PermissionServiceContext::DidNavigateAnyFrame(
+    RenderFrameHost* render_frame_host,
+    const LoadCommittedDetails& details,
+    const FrameNavigateParams& params) {
+  if (render_frame_host != render_frame_host_ || details.is_in_page)
+    return;
+
+  if (service_)
+    service_->CancelPendingRequests();
+}
+
+RenderFrameHost* PermissionServiceContext::render_frame_host() {
+  return render_frame_host_;
+}
+
+void PermissionServiceContext::set_service(PermissionServiceImpl* service) {
+  service_ = service;
+}
+
+} // namespace content