[core] Fixed annotation icon replacement

Another pass at #3146, including a unit test.

src/mbgl/map/map.cpp

@@ -392,7 +392,7 @@ void Map::addAnnotationIcon(const std::string& name, std::shared_ptr<const Sprit
 }
 
 void Map::removeAnnotationIcon(const std::string& name) {
-    removeAnnotationIcon(name);
+    context->invoke(&MapContext::removeAnnotationIcon, name);
 }
 
 double Map::getTopOffsetPixelsForAnnotationIcon(const std::string& symbol) {

src/mbgl/sprite/sprite_atlas.cpp

@@ -189,11 +189,10 @@ void SpriteAtlas::updateDirty() {
             holder.texture = spriteIterator->second;
             if (holder.texture != nullptr) {
                 copy(holder, imageIterator->first.second);
+                ++imageIterator;
             } else {
-                images.erase(imageIterator);
+                images.erase(imageIterator++);
             }
-            
-            ++imageIterator;
             // Don't advance the spriteIterator because there might be another sprite with the same
             // name, but a different wrap value.
         }

test/api/annotations.cpp

@@ -14,8 +14,8 @@
 
 using namespace mbgl;
 
-std::shared_ptr<SpriteImage> defaultMarker() {
-    PremultipliedImage image = decodeImage(util::read_file("test/fixtures/sprites/default_marker.png"));
+std::shared_ptr<SpriteImage> namedMarker(const std::string &name) {
+    PremultipliedImage image = decodeImage(util::read_file("test/fixtures/sprites/" + name));
     return std::make_shared<SpriteImage>(image.width, image.height, 1.0, std::string(reinterpret_cast<char*>(image.data.get()), image.size()));
 }
 
@@ -31,7 +31,7 @@ TEST(Annotations, PointAnnotation) {
 
     Map map(view, fileSource, MapMode::Still);
     map.setStyleJSON(util::read_file("test/fixtures/api/empty.json"), "");
-    map.addAnnotationIcon("default_marker", defaultMarker());
+    map.addAnnotationIcon("default_marker", namedMarker("default_marker.png"));
     map.addPointAnnotation(PointAnnotation({ 0, 0 }, "default_marker"));
 
     checkRendering(map, "point_annotation");
@@ -96,7 +96,7 @@ TEST(Annotations, AddMultiple) {
 
     Map map(view, fileSource, MapMode::Still);
     map.setStyleJSON(util::read_file("test/fixtures/api/empty.json"), "");
-    map.addAnnotationIcon("default_marker", defaultMarker());
+    map.addAnnotationIcon("default_marker", namedMarker("default_marker.png"));
     map.addPointAnnotation(PointAnnotation({ 0, -10 }, "default_marker"));
 
     test::render(map);
@@ -126,6 +126,25 @@ TEST(Annotations, NonImmediateAdd) {
     checkRendering(map, "non_immediate_add");
 }
 
+TEST(Annotations, UpdatePoint) {
+    auto display = std::make_shared<mbgl::HeadlessDisplay>();
+    HeadlessView view(display, 1);
+    DefaultFileSource fileSource(nullptr, test::getFileSourceRoot());
+
+    Map map(view, fileSource, MapMode::Still);
+    map.setStyleJSON(util::read_file("test/fixtures/api/empty.json"), "");
+    map.addAnnotationIcon("flipped_marker", namedMarker("default_marker.png"));
+    map.addPointAnnotation(PointAnnotation({ 0, 0 }, "flipped_marker"));
+
+    test::render(map);
+
+    map.removeAnnotationIcon("flipped_marker");
+    map.addAnnotationIcon("flipped_marker", namedMarker("flipped_marker.png"));
+    map.update(Update::Annotations);
+
+    checkRendering(map, "update_point");
+}
+
 TEST(Annotations, RemovePoint) {
     auto display = std::make_shared<mbgl::HeadlessDisplay>();
     HeadlessView view(display, 1);
@@ -133,7 +152,7 @@ TEST(Annotations, RemovePoint) {
 
     Map map(view, fileSource, MapMode::Still);
     map.setStyleJSON(util::read_file("test/fixtures/api/empty.json"), "");
-    map.addAnnotationIcon("default_marker", defaultMarker());
+    map.addAnnotationIcon("default_marker", namedMarker("default_marker.png"));
     uint32_t point = map.addPointAnnotation(PointAnnotation({ 0, 0 }, "default_marker"));
 
     test::render(map);
@@ -184,7 +203,7 @@ TEST(Annotations, SwitchStyle) {
 
     Map map(view, fileSource, MapMode::Still);
     map.setStyleJSON(util::read_file("test/fixtures/api/empty.json"), "");
-    map.addAnnotationIcon("default_marker", defaultMarker());
+    map.addAnnotationIcon("default_marker", namedMarker("default_marker.png"));
     map.addPointAnnotation(PointAnnotation({ 0, 0 }, "default_marker"));
 
     test::render(map);