filter: minor code cleanup

src/filter.hh

@@ -6,14 +6,13 @@
 #include "string.hh"
 #include "utils.hh"
 #include "memoryview.hh"
-#include "selection.hh"
 #include "function_registry.hh"
 
 namespace Kakoune
 {
 
 class Buffer;
-class BufferIterator;
+class Selection;
 
 // A Filter is a function which is applied to a Buffer and a pending
 // Modification in order to mutate the Buffer or the Modification

src/filters.cc

@@ -1,6 +1,7 @@
 #include "filters.hh"
 #include "buffer.hh"
 #include "filter_group.hh"
+#include "selection.hh"
 
 namespace Kakoune
 {