[core] Make the BackgroundScheduler a singleton

- Do not carry it over everywhere as parameter, it is a shared
  instance anyway and the lifecycle is pretty much the app lifecycle
  from the moment we instantiate a map.
- Rename to BackgroundScheduler because it is a Scheduler that will
  do tasks in the background, we don't make assumptions if it is a
  thread pool or a single thread.
- Most importantly, remove the dependency from `core` on `platform`.

1 files changed, 0 insertions, 2 deletions

diff --git a/src/mbgl/renderer/tile_parameters.hpp b/src/mbgl/renderer/tile_parameters.hpp
index 665c7490d2..cbe8dfb3ba 100644
--- a/src/mbgl/renderer/tile_parameters.hpp
+++ b/src/mbgl/renderer/tile_parameters.hpp
@@ -5,7 +5,6 @@
 namespace mbgl {
 
 class TransformState;
-class Scheduler;
 class FileSource;
 class AnnotationManager;
 class ImageManager;
@@ -16,7 +15,6 @@ public:
     const float pixelRatio;
     const MapDebugOptions debugOptions;
     const TransformState& transformState;
-    Scheduler& workerScheduler;
     FileSource& fileSource;
     const MapMode mode;
     AnnotationManager& annotationManager;