Roll src/third_party/leveldatabase/src/ d177a0263..e9098a131 (3 commits)

https://chromium.googlesource.com/external/leveldb.git/+log/d177a0263cce..e9098a1311a1

$ git log d177a0263..e9098a131 --date=short --no-merges --format='%ad %ae %s'
2018-04-19 costan Cleanup SnapshotImpl.
2018-03-10 costan Add YouCompleteMe configuration.
2018-04-23 costan Add move constructor to Status.

Created with:
  roll-dep src/third_party/leveldatabase/src

Change-Id: I9aad751c72ea10d81d06ca25ae98e1a6b0f095b4
Reviewed-on: https://chromium-review.googlesource.com/1033586Reviewed-by: Chris Mumford <cmumford@chromium.org>
Commit-Queue: Victor Costan <pwnall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#559223}

DEPS

@@ -707,7 +707,7 @@ deps = {
   },
 
   'src/third_party/leveldatabase/src':
-    Var('chromium_git') + '/external/leveldb.git' + '@' + 'd177a0263cce4344d05188521ad53459c369b940',
+    Var('chromium_git') + '/external/leveldb.git' + '@' + '18683981505dc374ce29211c80a9552f8f2f4571',
 
   'src/third_party/libFuzzer/src':
     Var('chromium_git') + '/chromium/llvm-project/compiler-rt/lib/fuzzer.git' + '@' +  Var('libfuzzer_revision'),