Don't treat empty raster tiles as valid

src/mbgl/tile/raster_tile.cpp

@@ -41,13 +41,13 @@ void RasterTile::setData(std::shared_ptr<const std::string> data,
 
 void RasterTile::onParsed(std::unique_ptr<Bucket> result) {
     bucket = std::move(result);
-    availableData = DataAvailability::All;
+    availableData = bucket ? DataAvailability::All : DataAvailability::None;
     observer->onTileChanged(*this);
 }
 
 void RasterTile::onError(std::exception_ptr err) {
     bucket.reset();
-    availableData = DataAvailability::All;
+    availableData = DataAvailability::None;
     observer->onTileError(*this, err);
 }
 

src/mbgl/tile/raster_tile_worker.cpp

@@ -1,6 +1,6 @@
 #include <mbgl/tile/raster_tile_worker.hpp>
 #include <mbgl/tile/raster_tile.hpp>
-#include <mbgl/renderer/raster_bucket.cpp>
+#include <mbgl/renderer/raster_bucket.hpp>
 #include <mbgl/actor/actor.hpp>
 #include <mbgl/util/premultiply.hpp>
 

test/tile/raster_tile.test.cpp

@@ -9,6 +9,7 @@
 #include <mbgl/style/style.hpp>
 #include <mbgl/style/update_parameters.hpp>
 #include <mbgl/annotation/annotation_manager.hpp>
+#include <mbgl/renderer/raster_bucket.hpp>
 
 using namespace mbgl;
 
@@ -45,5 +46,19 @@ TEST(RasterTile, onError) {
     RasterTileTest test;
     RasterTile tile(OverscaledTileID(0, 0, 0), test.updateParameters, test.tileset);
     tile.onError(std::make_exception_ptr(std::runtime_error("test")));
+    EXPECT_FALSE(tile.isRenderable());
+}
+
+TEST(RasterTile, onParsed) {
+    RasterTileTest test;
+    RasterTile tile(OverscaledTileID(0, 0, 0), test.updateParameters, test.tileset);
+    tile.onParsed(std::make_unique<RasterBucket>(UnassociatedImage{}));
     EXPECT_TRUE(tile.isRenderable());
 }
+
+TEST(RasterTile, onParsedEmpty) {
+    RasterTileTest test;
+    RasterTile tile(OverscaledTileID(0, 0, 0), test.updateParameters, test.tileset);
+    tile.onParsed(nullptr);
+    EXPECT_FALSE(tile.isRenderable());
+}