[core, android] Factor JSON string conversions

This adds a `convertJSON` template, to be used like:

   Error error
   optional<Foo> foo = convertJSON<Foo>(string, error);

Internally, it parses the string with RapidJSON and then calls `convert<Foo>(parsed, error)`.

While here, rationalize GeoJSON converters and fix error handling for Tileset conversion in OfflineDownload.

1 files changed, 1 insertions, 1 deletions

diff --git a/platform/qt/src/qmapboxgl.cpp b/platform/qt/src/qmapboxgl.cpp
index edb8afa28a..ce7e237afb 100644
--- a/platform/qt/src/qmapboxgl.cpp
+++ b/platform/qt/src/qmapboxgl.cpp
@@ -1303,7 +1303,7 @@ void QMapboxGL::updateSource(const QString &id, const QVariantMap &params)
 
     if (params.contains("data")) {
         Error error;
-        auto result = convertGeoJSON(params["data"], error);
+        auto result = convert<mbgl::GeoJSON>(params["data"], error);
         if (result) {
             sourceGeoJSON->setGeoJSON(*result);
         }