Implement basic mojo Permission service and use it for Geolocation.

content/browser/frame_host/render_frame_host_impl.cc

 // Copyright 2013 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/frame_host/render_frame_host_impl.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/containers/hash_tables.h"
 #include "base/lazy_instance.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/user_metrics_action.h"
 #include "base/time/time.h"
 #include "content/browser/accessibility/accessibility_mode_helper.h"
 #include "content/browser/accessibility/browser_accessibility_manager.h"
 #include "content/browser/accessibility/browser_accessibility_state_impl.h"
 #include "content/browser/child_process_security_policy_impl.h"
 #include "content/browser/frame_host/cross_process_frame_connector.h"
 #include "content/browser/frame_host/cross_site_transferring_request.h"
 #include "content/browser/frame_host/frame_accessibility.h"
 #include "content/browser/frame_host/frame_tree.h"
 #include "content/browser/frame_host/frame_tree_node.h"
 #include "content/browser/frame_host/navigator.h"
 #include "content/browser/frame_host/render_frame_host_delegate.h"
 #include "content/browser/frame_host/render_frame_proxy_host.h"
 #include "content/browser/frame_host/render_widget_host_view_child_frame.h"
 #include "content/browser/geolocation/geolocation_service_context.h"
+#include "content/browser/permissions/permission_service_context.h"
+#include "content/browser/permissions/permission_service_impl.h"
 #include "content/browser/renderer_host/input/input_router.h"
 #include "content/browser/renderer_host/input/timeout_monitor.h"
 #include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/browser/renderer_host/render_view_host_delegate.h"
 #include "content/browser/renderer_host/render_view_host_delegate_view.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/browser/renderer_host/render_widget_host_view_base.h"
 #include "content/browser/transition_request_manager.h"
 #include "content/common/accessibility_messages.h"
@@ skipping 1222 matching lines @@
   if (geolocation_service_context) {
     // TODO(creis): Bind process ID here so that GeolocationServiceImpl
     // can perform permissions checks once site isolation is complete.
     // crbug.com/426384
     GetServiceRegistry()->AddService<GeolocationService>(
         base::Bind(&GeolocationServiceContext::CreateService,
                    base::Unretained(geolocation_service_context),
                    base::Bind(&RenderFrameHostImpl::DidUseGeolocationPermission,
                               base::Unretained(this))));
   }
+
+  scoped_ptr<PermissionServiceContext> permission_service_context(
+      new PermissionServiceContext(this));
+  GetServiceRegistry()->AddService(
+      base::Bind(&PermissionServiceImpl::Create,
+                 base::Passed(&permission_service_context)));

[qsr, 2014/11/14 09:20:26]

This callback will be run each time something connect to the permission service.
Given that the first call will pass the context to the first instance, all other
instance will have a null context.

[mlamouri (slow - plz ping), 2014/11/14 11:37:11]

I might need some deeper understanding on how things work. My understanding was
that there would be one service per RFH. Do you mean that there is one service
instance per clients? Maybe in our case it doesn't change much because there is
a 1:1 relationship betweer RF/RFH?

[qsr, 2014/11/14 11:49:27]

 What you register is a factory. Each time something will request a connection
to the service, the factory will be called. So you need to consider that it will
be called more than once. That's why you should share the context between all
the instances. What Collin was suggesting (and I agree) is to have the context
owned by the RFH. It can then have the factory method itself, and each time it
creates a service, it owns it (using WeakBind instead of Bind), and delete all
of those when it is killed. It should also monitor the service for connection
error and delete those that go into an error state.

 }
 
 void RenderFrameHostImpl::SetState(RenderFrameHostImplState rfh_state) {
   // Only main frames should be swapped out and retained inside a proxy host.
   if (rfh_state == STATE_SWAPPED_OUT)
     CHECK(!GetParent());
 
   // We update the number of RenderFrameHosts in a SiteInstance when the swapped
   // out status of a RenderFrameHost gets flipped to/from active.
   if (!IsRFHStateActive(rfh_state_) && IsRFHStateActive(rfh_state))
@@ skipping 418 matching lines @@
 void RenderFrameHostImpl::DidUseGeolocationPermission() {
   RenderFrameHost* top_frame = frame_tree_node()->frame_tree()->GetMainFrame();
   GetContentClient()->browser()->RegisterPermissionUsage(
       PERMISSION_GEOLOCATION,
       delegate_->GetAsWebContents(),
       GetLastCommittedURL().GetOrigin(),
       top_frame->GetLastCommittedURL().GetOrigin());
 }
 
 }  // namespace content