[core] Modularize FileSource codebase (#15768)

* [core] Introduce FileSourceManager and use it for default platform impl

  - Add `FileSourceManager` interface that provides access to `FileSource`
    instances and means of registering / unregistering `FileSource` factories
  - Split `DefaultFileSource` into smaller parts
  - Add `DatabaseFileSource` interface and it's default implementation
  - Remove inter-dependencies between concrete `FileSource` classes

* [build] Add files to next build system

* [core] Add generic property setters / getters

* [core] Remove setOnlineStatus from OnlineFileSource interface

* [core] Hide threading implementation details from DatabaseFileSource interface

* [core] Make DB file source methods virtual

* [core] Add documentation for DatabaseFileSource and rename one method

* [core] Use simple callback instead of ActorRef

* [core] Remove ActorRef from OnlineFileSource public header

* [core] Add callback to FileSource::forward async API

* [core] Pass OfflineRegionDefinition by value

* [core] Update tests to use modular file sources

* [core] Update unit tests

* [core] Update unit tests after rebase

* [core] Backport low prio fix for cached requests

* [core] Backport pack database

* [core] Return removed factory from unRegisterFileSourceFactory

* [core] Rename shadowed args in onlinefilesource

* [core] Remove simple std::function callback aliases

* [core] Expose online file source property keys in public header file

* [test-runner] Add proxy file source test runner

* [cache] Update mbgl-cache utility to use new file source

* [metrics] Rebaseline binary size metrics

* [offline] Update offline utility

* [core] Update changelog

6 files changed, 6 insertions, 6 deletions

diff --git a/test/tile/custom_geometry_tile.test.cpp b/test/tile/custom_geometry_tile.test.cpp
index fb905ac076..f3d11ab898 100644
--- a/test/tile/custom_geometry_tile.test.cpp
+++ b/test/tile/custom_geometry_tile.test.cpp
@@ -25,7 +25,7 @@ public:
     std::shared_ptr<FileSource> fileSource = std::make_shared<FakeFileSource>();
     TransformState transformState;
     util::RunLoop loop;
-    style::Style style { *fileSource, 1 };
+    style::Style style{fileSource, 1};
     AnnotationManager annotationManager { style };
     ImageManager imageManager;
     GlyphManager glyphManager;
diff --git a/test/tile/geojson_tile.test.cpp b/test/tile/geojson_tile.test.cpp
index d4bf1e0752..25fd268dc8 100644
--- a/test/tile/geojson_tile.test.cpp
+++ b/test/tile/geojson_tile.test.cpp
@@ -25,7 +25,7 @@ public:
     std::shared_ptr<FileSource> fileSource = std::make_shared<FakeFileSource>();
     TransformState transformState;
     util::RunLoop loop;
-    style::Style style { *fileSource, 1 };
+    style::Style style{fileSource, 1};
     AnnotationManager annotationManager { style };
     ImageManager imageManager;
     GlyphManager glyphManager;
diff --git a/test/tile/raster_dem_tile.test.cpp b/test/tile/raster_dem_tile.test.cpp
index 42e7594720..f5f7610096 100644
--- a/test/tile/raster_dem_tile.test.cpp
+++ b/test/tile/raster_dem_tile.test.cpp
@@ -19,7 +19,7 @@ public:
     std::shared_ptr<FileSource> fileSource = std::make_shared<FakeFileSource>();
     TransformState transformState;
     util::RunLoop loop;
-    style::Style style { *fileSource, 1 };
+    style::Style style{fileSource, 1};
     AnnotationManager annotationManager { style };
     ImageManager imageManager;
     GlyphManager glyphManager;
diff --git a/test/tile/raster_tile.test.cpp b/test/tile/raster_tile.test.cpp
index f19bd26260..a5a2875f2e 100644
--- a/test/tile/raster_tile.test.cpp
+++ b/test/tile/raster_tile.test.cpp
@@ -19,7 +19,7 @@ public:
     std::shared_ptr<FileSource> fileSource = std::make_shared<FakeFileSource>();
     TransformState transformState;
     util::RunLoop loop;
-    style::Style style { *fileSource, 1 };
+    style::Style style{fileSource, 1};
     AnnotationManager annotationManager { style };
     ImageManager imageManager;
     GlyphManager glyphManager;
diff --git a/test/tile/tile_cache.test.cpp b/test/tile/tile_cache.test.cpp
index 7a89ece756..43b409ae87 100644
--- a/test/tile/tile_cache.test.cpp
+++ b/test/tile/tile_cache.test.cpp
@@ -28,7 +28,7 @@ public:
     std::shared_ptr<FileSource> fileSource = std::make_shared<FakeFileSource>();
     TransformState transformState;
     util::RunLoop loop;
-    style::Style style{*fileSource, 1};
+    style::Style style{fileSource, 1};
     AnnotationManager annotationManager{style};
     ImageManager imageManager;
     GlyphManager glyphManager;
diff --git a/test/tile/vector_tile.test.cpp b/test/tile/vector_tile.test.cpp
index 940c0272db..d282c874ef 100644
--- a/test/tile/vector_tile.test.cpp
+++ b/test/tile/vector_tile.test.cpp
@@ -25,7 +25,7 @@ public:
     std::shared_ptr<FileSource> fileSource = std::make_shared<FakeFileSource>();
     TransformState transformState;
     util::RunLoop loop;
-    style::Style style { *fileSource, 1 };
+    style::Style style{fileSource, 1};
     AnnotationManager annotationManager { style };
     ImageManager imageManager;
     GlyphManager glyphManager;