Synchronize map updates with traffic manager

Signed-off-by: mvglasow <michael -at- vonglasow.com>

map/framework.cpp

@@ -443,13 +443,13 @@ void Framework::OnCountryFileDownloaded(storage::CountryId const &,
   m2::RectD rect = mercator::Bounds::FullRect();
 
   if (localFile && localFile->OnDisk(MapFileType::Map))
-  {
+    m_trafficManager.RunSynchronized([this, localFile, &rect](){
       auto const res = RegisterMap(*localFile);
       MwmSet::MwmId const & id = res.first;
       if (id.IsAlive())
         rect = id.GetInfo()->m_bordersRect;
       m_trafficManager.Invalidate(id);
-  }
+    });
 
   m_transitManager.Invalidate();
   m_isolinesManager.Invalidate();

map/traffic_manager.cpp

@@ -301,9 +301,6 @@ void TrafficManager::Invalidate(MwmSet::MwmId const & mwmId)
   auto const mwmRect = mwmId.GetInfo()->m_bordersRect; // m2::RectD
   traffxml::TraffFeed invalidated;
 
-  {
-    std::lock_guard<std::mutex> lock(m_mutex);
-
   for (auto it = m_messageCache.begin(); it != m_messageCache.end(); )
   {
     if (!it->second.m_location)
@@ -349,7 +346,6 @@ void TrafficManager::Invalidate(MwmSet::MwmId const & mwmId)
     m_condition.notify_one();
   }
 }
-}
 
 void TrafficManager::UpdateActiveMwms(m2::RectD const & rect,
                                       std::vector<MwmSet::MwmId> & lastMwmsByRect,

map/traffic_manager.hpp

@@ -224,6 +224,9 @@ public:
    * for these locations are discarded and decoded again, ensuring they are based on the new MWM.
    * The TraFF messages themselves remain unchanged.
    *
+   * This method must either be called from a lambda function passed to `RunSynchronized()`,
+   * or the caller must explicitly lock the private `m_mutex` prior to calling this method.
+   *
    * @param mwmId The newly addded MWM.
    */
   void Invalidate(MwmSet::MwmId const & mwmId);
@@ -313,6 +316,19 @@ public:
    */
   void SetTrafficUpdateCallbackFn(TrafficUpdateCallbackFn && fn);
 
+  /**
+   * @brief Runs a function guarded by the traffic manager mutex.
+   *
+   * This locks `m_mutex`, then runs `f` and releases the mutex.
+   *
+   * @param f
+   */
+  void RunSynchronized(std::function<void()> f)
+  {
+    std::lock_guard<std::mutex> lock(m_mutex);
+    f();
+  }
+
 private:
 
   /**