[update_engine] Update to use not-hideously-old logging API from chrome

BUG=None
TEST=compile

Change-Id: Ieed8952b6806a72b59e16c1579f7293b6a98157a

Review URL: http://codereview.chromium.org/3170010
diff --git a/libcurl_http_fetcher.cc b/libcurl_http_fetcher.cc
index 3ae5fbf..7bee4c1 100644
--- a/libcurl_http_fetcher.cc
+++ b/libcurl_http_fetcher.cc
@@ -4,7 +4,7 @@
 
 #include "update_engine/libcurl_http_fetcher.h"
 #include <algorithm>
-#include "chromeos/obsolete_logging.h"
+#include "base/logging.h"
 
 using std::max;
 using std::make_pair;