[core] don't mark tiles with failed requests as obsolete

Otherwise, this will remove them from the map and overwrite the old data. This could happen e.g. when we have connection trouble and a tile needs to be refreshed, or we're displaying stale information and the connection is down.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/mbgl/map/tile_data.hpp b/src/mbgl/map/tile_data.hpp
index 2bb11054a6..e31cced964 100644
--- a/src/mbgl/map/tile_data.hpp
+++ b/src/mbgl/map/tile_data.hpp
@@ -88,6 +88,10 @@ public:
         return state;
     }
 
+    bool hasError() const {
+        return error.operator bool();
+    }
+
     std::exception_ptr getError() const {
         return error;
     }