permissions: handle request ids for permissions in permission manager

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 "base/bind.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/permission_manager.h"
 #include "content/public/browser/permission_type.h"
@@ skipping 27 matching lines @@
   NOTREACHED();
   return PermissionType::NUM;
 }
 
 } // anonymous namespace
 
 PermissionServiceImpl::PendingRequest::PendingRequest(
     PermissionType permission,
     const GURL& origin,
     const PermissionStatusCallback& callback)
-    : permission(permission),
+    : id(-1),

[mlamouri (slow - plz ping), 2015/09/23 14:46:00]

I think you could use the constant here.

[Lalit Maganti, 2015/09/23 15:24:30]

Done.

+      permission(permission),
       origin(origin),
       callback(callback) {
 }
 
 PermissionServiceImpl::PendingRequest::~PendingRequest() {
   if (!callback.is_null())
     callback.Run(PERMISSION_STATUS_ASK);
 }
 
 PermissionServiceImpl::PendingSubscription::PendingSubscription(
@@ skipping 51 matching lines @@
   }
 
   BrowserContext* browser_context = context_->GetBrowserContext();
   DCHECK(browser_context);
   if (!browser_context->GetPermissionManager()) {
     callback.Run(content::PERMISSION_STATUS_DENIED);
     return;
   }
 
   PermissionType permission_type = PermissionNameToPermissionType(permission);
-  int request_id = pending_requests_.Add(
+  int pending_request_id = pending_requests_.Add(
       new PendingRequest(permission_type, GURL(origin), callback));
 
-  browser_context->GetPermissionManager()->RequestPermission(
+  int id = browser_context->GetPermissionManager()->RequestPermission(
       permission_type,
       context_->render_frame_host(),
-      request_id,
       GURL(origin),
       user_gesture, // TODO(mlamouri): should be removed (crbug.com/423770)
       base::Bind(&PermissionServiceImpl::OnRequestPermissionResponse,
                  weak_factory_.GetWeakPtr(),
-                 request_id));
+                 pending_request_id));
+
+  // Check if the request still exists. It may have been removed by the
+  // the response callback.

[mlamouri (slow - plz ping), 2015/09/23 14:46:00]

nit: could you rephrase to explain that the callback might have been run
synchronously.

[Lalit Maganti, 2015/09/23 15:24:30]

Done.

+  PendingRequest* pending_request = pending_requests_.Lookup(
+      pending_request_id);
+  if (!pending_request)
+      return;
+  pending_request->id = id;
 }
 
 void PermissionServiceImpl::RequestPermissions(
     mojo::Array<PermissionName> permissions,
     const mojo::String& origin,
     bool user_gesture,
     const PermissionsStatusCallback& callback) {
   NOTIMPLEMENTED();
 
   // TODO(lalitm,mlamouri): this is returning the current permission statuses
   // in order for the call to successfully return. It will be changed later.
   // See https://crbug.com/516626
   mojo::Array<PermissionStatus> result(permissions.size());
   for (size_t i = 0; i < permissions.size(); ++i)
     result[i] = GetPermissionStatusFromName(permissions[i], GURL(origin));
   callback.Run(result.Pass());
 }
 
 void PermissionServiceImpl::OnRequestPermissionResponse(
     int request_id,
     PermissionStatus status) {
   PendingRequest* request = pending_requests_.Lookup(request_id);
   PermissionStatusCallback callback(request->callback);
   request->callback.reset();
   pending_requests_.Remove(request_id);
   callback.Run(status);
 }
 
 void PermissionServiceImpl::CancelPendingOperations() {
-  DCHECK(context_->render_frame_host());
   DCHECK(context_->GetBrowserContext());
 
   PermissionManager* permission_manager =
       context_->GetBrowserContext()->GetPermissionManager();
   if (!permission_manager)
     return;
 
   // Cancel pending requests.
   for (RequestsMap::Iterator<PendingRequest> it(&pending_requests_);
        !it.IsAtEnd(); it.Advance()) {
     permission_manager->CancelPermissionRequest(
-        it.GetCurrentValue()->permission,
-        context_->render_frame_host(),
-        it.GetCurrentKey(),
-        it.GetCurrentValue()->origin);
+        it.GetCurrentValue()->id);
   }
   pending_requests_.Clear();
 
   // Cancel pending subscriptions.
   for (SubscriptionsMap::Iterator<PendingSubscription>
           it(&pending_subscriptions_); !it.IsAtEnd(); it.Advance()) {
     it.GetCurrentValue()->callback.Run(GetPermissionStatusFromType(
         it.GetCurrentValue()->permission, it.GetCurrentValue()->origin));
     it.GetCurrentValue()->callback.reset();
     permission_manager->UnsubscribePermissionStatusChange(
@@ skipping 118 matching lines @@
 
   PermissionStatusCallback callback = subscription->callback;
 
   subscription->callback.reset();
   pending_subscriptions_.Remove(pending_subscription_id);
 
   callback.Run(status);
 }
 
 }  // namespace content