Keep updating until all the tiles are State::parsed

This is needed because of a race that can occur now that we
requests Glyphs from the Map Thread:

The glyph might arrive at the moment a tile is being parsed
and they won't be notified again of any new data, remaining
forever at the partial state.

src/mbgl/map/source.cpp

@@ -240,14 +240,8 @@ bool Source::handlePartialTile(const TileID& id, Worker&) {
         return true;
     }
 
-    // The signal is only emitted if there was an actual change on the tile. The
-    // tile can be in a "partial" state waiting for resources and get reparsed on
-    // the arrival of new resources that were needed by another tile.
-    size_t bucketCount = data->countBuckets();
-    return data->reparse([this, data, bucketCount]() {
-        if (data->countBuckets() > bucketCount) {
-            emitTileLoaded(false);
-        }
+    return data->reparse([this, data]() {
+	emitTileLoaded(false);
     });
 }
 

src/mbgl/map/tile_worker.cpp

@@ -44,11 +44,6 @@ Bucket* TileWorker::getBucket(const StyleLayer& layer) const {
     return it->second.get();
 }
 
-size_t TileWorker::countBuckets() const {
-    std::lock_guard<std::mutex> lock(bucketsMutex);
-    return buckets.size();
-}
-
 TileParseResult TileWorker::parse(const GeometryTile& geometryTile) {
     partialParse = false;
 

src/mbgl/map/tile_worker.hpp

@@ -41,7 +41,6 @@ public:
     ~TileWorker();
 
     Bucket* getBucket(const StyleLayer&) const;
-    size_t countBuckets() const;
 
     TileParseResult parse(const GeometryTile&);
     void redoPlacement(float angle, bool collisionDebug);

src/mbgl/map/vector_tile_data.cpp

@@ -98,10 +98,6 @@ Bucket* VectorTileData::getBucket(const StyleLayer& layer) {
     return tileWorker.getBucket(layer);
 }
 
-size_t VectorTileData::countBuckets() const {
-    return tileWorker.countBuckets();
-}
-
 void VectorTileData::redoPlacement(float angle, bool collisionDebug) {
     if (angle == currentAngle && collisionDebug == currentCollisionDebug)
         return;

src/mbgl/map/vector_tile_data.hpp

@@ -23,7 +23,6 @@ public:
     ~VectorTileData();
 
     Bucket* getBucket(const StyleLayer&) override;
-    size_t countBuckets() const;
 
     void request(float pixelRatio,
                  const std::function<void()>& callback);