AU: Try delta updates first, then full updates

src/platform/update_engine/filesystem_copier_action.cc

Index: src/platform/update_engine/filesystem_copier_action.cc
diff --git a/src/platform/update_engine/filesystem_copier_action.cc b/src/platform/update_engine/filesystem_copier_action.cc
index 875df9508b2c6742303c6617ce7c2975bc9272c9..f9b6869fc8314115539512e08d957b980b7f31ad 100644
--- a/src/platform/update_engine/filesystem_copier_action.cc
+++ b/src/platform/update_engine/filesystem_copier_action.cc
@@ -9,12 +9,14 @@
 #include <fcntl.h>
 #include <stdlib.h>
 #include <algorithm>
+#include <map>
 #include <string>
 #include <vector>
 #include "update_engine/filesystem_iterator.h"
 #include "update_engine/subprocess.h"
 #include "update_engine/utils.h"
 
+using std::map;
 using std::min;
 using std::string;
 using std::vector;