commit c1cea9e10ffec54d0f675478e541ee4a6e87f653
Author: Tom Hughes <tom@compton.nu>
Date:   Wed Jun 5 18:45:57 2013 +0100

    Use system sparsehash

diff --git a/include/mapnik/palette.hpp b/include/mapnik/palette.hpp
index 5f96272..44d06aa 100644
--- a/include/mapnik/palette.hpp
+++ b/include/mapnik/palette.hpp
@@ -33,7 +33,7 @@
 #pragma GCC diagnostic push
 #include <mapnik/warning_ignore.hpp>
 #ifdef USE_DENSE_HASH_MAP
-#include <mapnik/sparsehash/dense_hash_map>
+#include <google/dense_hash_map>
 using rgba_hash_table = google::dense_hash_map<unsigned int, unsigned char>;
 #else
 #include <unordered_map>