Fix TileJSON conversion to allow single point bounds

src/mbgl/style/conversion/tileset.cpp

@@ -95,12 +95,12 @@ optional<Tileset> Converter<Tileset>::operator()(const Convertible& value, Error
 
         bottom = util::clamp(*bottom, -90.0, 90.0);
         top = util::clamp(*top, -90.0, 90.0);
-        if (top <= bottom){
+        if (*top < *bottom){
             error.message = "bounds bottom latitude must be smaller than top latitude";
             return nullopt;
         }
 
-        if(*left >= *right) {
+        if(*left > *right) {
             error.message = "bounds left longitude should be less than right longitude";
             return nullopt;
         }

test/style/conversion/tileset.test.cpp

@@ -62,6 +62,16 @@ TEST(Tileset, ValidWorldBounds) {
     EXPECT_EQ(converted->bounds, LatLngBounds::hull({90, -180}, {-90, 180}));
 }
 
+TEST(Tileset, PointBounds) {
+    Error error;
+    mbgl::optional<Tileset> converted = convertJSON<Tileset>(R"JSON({
+        "tiles": ["http://mytiles"],
+        "bounds": [0, 0, 0, 0]
+    })JSON", error);
+    EXPECT_TRUE((bool) converted);
+    EXPECT_EQ(converted->bounds, LatLngBounds::hull({0, 0}, {0, 0}));
+}
+
 TEST(Tileset, BoundsAreClamped) {
     Error error;
     mbgl::optional<Tileset> converted = convertJSON<Tileset>(R"JSON({