[core] Remove tile sorting from the clip and mask algorithms

The tile sorting can be now removed from the algorithms, which
calculate tile mask and clip ids, because their client code
provides tiles being already sorted (in `TilePyramid`).

This patch brings significant improvements to the Tile-related
performance tests results, for example the `TileMaskGeneration`
benchmark test runs 33 times faster with these changes applied.

1 files changed, 3 insertions, 4 deletions

diff --git a/src/mbgl/algorithm/generate_clip_ids_impl.hpp b/src/mbgl/algorithm/generate_clip_ids_impl.hpp
index fedab06022..a4af9c8cbb 100644
--- a/src/mbgl/algorithm/generate_clip_ids_impl.hpp
+++ b/src/mbgl/algorithm/generate_clip_ids_impl.hpp
@@ -10,12 +10,11 @@ namespace algorithm {
 template <typename Renderable>
 void ClipIDGenerator::update(std::vector<std::reference_wrapper<Renderable>> renderables) {
     std::size_t size = 0;
-
-    std::sort(renderables.begin(), renderables.end(),
-              [](const auto& a, const auto& b) { return a.get().id < b.get().id; });
+    assert(std::is_sorted(renderables.begin(), renderables.end(),
+        [](const Renderable& a, const Renderable& b) { return a.id < b.id; }));
 
     const auto end = renderables.end();
-    for (auto it = renderables.begin(); it != end; it++) {
+    for (auto it = renderables.begin(); it != end; ++it) {
         auto& renderable = it->get();
         if (!renderable.used || !renderable.needsClipping) {
             continue;