Roll src/third_party/leveldatabase/src/ 53e280b56..2c9c80bd5 (18 commits)

https://chromium.googlesource.com/external/leveldb.git/+log/53e280b56866..2c9c80bd539c

$ git log 53e280b56..2c9c80bd5 --date=short --no-merges --format='%ad %ae %s'
2019-11-11 costan Move CI to Visual Studio 2019.
2019-11-10 costan Allow different C/C++ standards when this is used as a subproject.
2019-11-07 costan Align CMake configuration with related projects.
2019-11-05 costan Remove redundant PROJECT_SOURCE_DIR usage from CMake config.
2019-11-04 costan Fix installed target definition.
2019-11-03 costan Test CMake installation on Travis.
2019-10-28 cmumford Renamed local variable in DBImpl::Write.
2019-10-02 cmumford Added return in Version::Get::State::Match to quiet warning.
2019-10-01 cmumford Using CMake's check_cxx_compiler_flag to check support for -Wthread-safety.
2019-09-29 costan Update Travis CI configuration.
2019-09-10 sanjay Fix tsan problem in env_test.
2019-08-28 13126959424 drop fileds in State that are duplicates of fileds in Saver and fix typo
2019-06-12 13126959424 cache Saver in State object
2019-06-12 13126959424 fix bug(uninitialized options pointer in State)
2019-06-11 13126959424 remove TODO in Version::ForEachOverlapping
2019-06-11 13126959424 format
2019-06-11 13126959424 fix bug
2019-06-11 13126959424 use ForEachOverlapping to impl Get

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

Tbr: cmumford
Change-Id: I8bc46032fdfe5a5988f52b1621c045d6f83a193f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1943311Reviewed-by: Victor Costan <pwnall@chromium.org>
Commit-Queue: Victor Costan <pwnall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#720304}

DEPS

@@ -1121,7 +1121,7 @@ deps = {
   },
 
   'src/third_party/leveldatabase/src':
-    Var('chromium_git') + '/external/leveldb.git' + '@' + '53e280b56866ac4c90a9f5fcfe02ebdfd4a19832',
+    Var('chromium_git') + '/external/leveldb.git' + '@' + '2c9c80bd539ca5aad5ea864ee6dd81c1ee3eb91e',
 
   'src/third_party/libFuzzer/src':
     Var('chromium_git') + '/chromium/llvm-project/compiler-rt/lib/fuzzer.git' + '@' +  Var('libfuzzer_revision'),