Roll LevelDB 54:55.

BUG=none

Review URL: http://codereview.chromium.org/8564013

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@109939 0039d316-1c4b-4281-b951-d872f2087c98

DEPS

@@ -83,7 +83,7 @@ deps = {
     "/trunk/src/google@143",
 
   "src/third_party/leveldatabase/src":
-    (Var("googlecode_url") % "leveldb") + "/trunk@54",
+    (Var("googlecode_url") % "leveldb") + "/trunk@55",
 
   "src/third_party/snappy/src":
     (Var("googlecode_url") % "snappy") + "/trunk@37",