Provide a callback for Component Updater OnDemand calls.

components/component_updater/component_updater_service.cc

Index: components/component_updater/component_updater_service.cc
diff --git a/components/component_updater/component_updater_service.cc b/components/component_updater/component_updater_service.cc
index 4964bb07c94339a094cbb3a7c2bf7da970990112..9d3d9c0512cd6e12a2bae5fc376f19cc8df5cebd 100644
--- a/components/component_updater/component_updater_service.cc
+++ b/components/component_updater/component_updater_service.cc
@@ -239,13 +239,19 @@ void CrxUpdateService::MaybeThrottle(const std::string& id,
   callback.Run();  // Unblock the request if the request can't be throttled.
 }
 
-bool CrxUpdateService::OnDemandUpdate(const std::string& id) {
+void CrxUpdateService::OnDemandUpdate(const std::string& id,
+                                      CompletionCallback callback) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
-  if (!GetComponent(id))
-    return false;
+  if (!GetComponent(id)) {
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE,
+        base::Bind(callback,
+                   update_client::Error::ERROR_UPDATE_INVALID_ARGUMENT));
+    return;
+  }
 
-  return OnDemandUpdateInternal(id);
+  OnDemandUpdateInternal(id, callback);
 }
 
 bool CrxUpdateService::OnDemandUpdateWithCooldown(const std::string& id) {
@@ -261,21 +267,20 @@ bool CrxUpdateService::OnDemandUpdateWithCooldown(const std::string& id) {
       return false;
   }
 
-  return OnDemandUpdateInternal(id);
+  OnDemandUpdateInternal(id, CompletionCallback());
+  return true;
 }
 
-bool CrxUpdateService::OnDemandUpdateInternal(const std::string& id) {
+void CrxUpdateService::OnDemandUpdateInternal(const std::string& id,
+                                              CompletionCallback callback) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   UMA_HISTOGRAM_ENUMERATION("ComponentUpdater.Calls", UPDATE_TYPE_MANUAL,
                             UPDATE_TYPE_COUNT);
-
   update_client_->Install(
       id, base::Bind(&CrxUpdateService::OnUpdate, base::Unretained(this)),
       base::Bind(&CrxUpdateService::OnUpdateComplete, base::Unretained(this),
-                 base::TimeTicks::Now()));
-
-  return true;
+                 callback, base::TimeTicks::Now()));
 }
 
 bool CrxUpdateService::CheckForUpdates() {
@@ -301,7 +306,7 @@ bool CrxUpdateService::CheckForUpdates() {
         unsecure_ids,
         base::Bind(&CrxUpdateService::OnUpdate, base::Unretained(this)),
         base::Bind(&CrxUpdateService::OnUpdateComplete, base::Unretained(this),
-                   base::TimeTicks::Now()));
+                   CompletionCallback(), base::TimeTicks::Now()));
   }
 
   if (!secure_ids.empty()) {
@@ -309,7 +314,7 @@ bool CrxUpdateService::CheckForUpdates() {
         secure_ids,
         base::Bind(&CrxUpdateService::OnUpdate, base::Unretained(this)),
         base::Bind(&CrxUpdateService::OnUpdateComplete, base::Unretained(this),
-                   base::TimeTicks::Now()));
+                   CompletionCallback(), base::TimeTicks::Now()));
   }
 
   return true;
@@ -354,7 +359,8 @@ void CrxUpdateService::OnUpdate(const std::vector<std::string>& ids,
   }
 }
 
-void CrxUpdateService::OnUpdateComplete(const base::TimeTicks& start_time,
+void CrxUpdateService::OnUpdateComplete(CompletionCallback callback,
+                                        const base::TimeTicks& start_time,
                                         int error) {
   DCHECK(thread_checker_.CalledOnValidThread());
   VLOG(1) << "Update completed with error " << error;
@@ -370,6 +376,11 @@ void CrxUpdateService::OnUpdateComplete(const base::TimeTicks& start_time,
         DoUnregisterComponent(*component);
     }
   }
+
+  if (static_cast<bool>(callback)) {

[Bernhard Bauer, 2016/08/19 04:13:05]

Just `if (callback)`? Or if you want to be explicit, !callback.is_null().

[Sorin Jianu, 2016/08/19 04:23:36]

Callback has an explicit conversion to bool. Will change the code to use the
null test.

+    base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE,
+                                                  base::Bind(callback, error));
+  }
 }
 
 void CrxUpdateService::OnEvent(Events event, const std::string& id) {