Implement basic mojo Permission service and use it for Geolocation.

content/browser/permissions/permission_service_impl.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_impl.h"
+
+#include "content/browser/geolocation/geolocation_provider_impl.h"
+#include "content/public/browser/content_browser_client.h"

[blundell, 2014/11/14 12:48:08]

I would still prefer that you push these //content dependencies into
PermissionServiceContext, as I described in my first review.

[mlamouri (slow - plz ping), 2014/11/14 13:39:42]

If we want to do something like that, we could rename the context a delegate and
move the entire logic there. I suggest to do that later based on need.

+#include "content/public/browser/render_process_host.h"
+
+namespace content {
+
+namespace {
+
+PermissionType PermissionNameToPermissionType(PermissionName name) {
+  switch(name) {
+    case PERMISSION_NAME_GEOLOCATION:
+      return PERMISSION_GEOLOCATION;
+  }
+
+  NOTREACHED();
+  return PERMISSION_NUM;
+}
+
+} // anonymous namespace
+
+PermissionServiceImpl::PendingRequest::PendingRequest(PermissionType permission,
+                                                      const GURL& origin)
+    : permission(permission),
+      origin(origin) {
+}
+
+PermissionServiceImpl::PermissionServiceImpl(PermissionServiceContext* context)
+    : context_(context),
+      weak_factory_(this) {
+}
+
+PermissionServiceImpl::~PermissionServiceImpl() {
+}
+
+void PermissionServiceImpl::OnConnectionError() {
+  context_->ServiceHadConnectionError(this);
+  // After that call, |this| will be deleted.
+}
+
+void PermissionServiceImpl::RequestPermission(
+    PermissionName permission,
+    const mojo::String& origin,
+    const mojo::Callback<void(PermissionStatus)>& callback) {
+  // This condition is valid if the call is coming from a ChildThread instead of
+  // a RenderFrame. Some consumers of the service run in Workers and some in
+  // Frames. In the context of a Worker, it is not possible to show a
+  // permission prompt because there is no tab. In the context of a Frame, we
+  // can. Even if the call comes from a context where it is not possible to show
+  // any UI, we want to still return something relevant so the current
+  // permission status is returned.
+  if (!context_->web_contents()) {
+    // There is no way to show a UI so the call will simply return the current
+    // permission.
+    QueryPermission(permission, origin, callback);
+    return;
+  }
+
+  PermissionType permission_type = PermissionNameToPermissionType(permission);
+  int request_id = pending_requests_.Add(
+      new PendingRequest(permission_type, GURL(origin)));
+
+  GetContentClient()->browser()->RequestPermission(
+      permission_type,
+      context_->web_contents(),
+      request_id,
+      GURL(origin),
+      true, // TODO(mlamouri): should be removed, see http://crbug.com/423770
+      base::Bind(&PermissionServiceImpl::OnRequestPermissionResponse,
+                 weak_factory_.GetWeakPtr(),
+                 callback,
+                 request_id));
+}
+
+void PermissionServiceImpl::OnRequestPermissionResponse(
+    const mojo::Callback<void(PermissionStatus)>& callback,
+    int request_id,
+    bool allowed) {
+  // TODO(mlamouri): we might want a generic way to handle those things.
+  if (allowed &&
+      pending_requests_.Lookup(request_id)->permission ==
+          PERMISSION_GEOLOCATION) {
+    GeolocationProviderImpl::GetInstance()->UserDidOptIntoLocationServices();
+  }
+
+  pending_requests_.Remove(request_id);
+
+  // TODO(mlamouri): for now, we only get a boolean back, but we would ideally
+  // need a ContentSetting, see http://crbug.com/432978
+  callback.Run(allowed ? PERMISSION_STATUS_GRANTED : PERMISSION_STATUS_ASK);
+}
+
+void PermissionServiceImpl::CancelPendingRequests() {
+  DCHECK(context_->web_contents());
+
+  for (RequestsMap::Iterator<PendingRequest> it(&pending_requests_);
+       !it.IsAtEnd(); it.Advance()) {
+    GetContentClient()->browser()->CancelPermissionRequest(
+        it.GetCurrentValue()->permission,
+        context_->web_contents(),
+        it.GetCurrentKey(),
+        it.GetCurrentValue()->origin);
+  }
+
+  pending_requests_.Clear();
+}
+
+void PermissionServiceImpl::QueryPermission(
+    PermissionName permission,
+    const mojo::String& origin,
+    const mojo::Callback<void(PermissionStatus)>& callback) {
+  NOTIMPLEMENTED();
+}
+
+}  // namespace content