Roll src/third_party/leveldatabase/src/ ffabb1ae8..3dc9202f7 (4 commits)

https://chromium.googlesource.com/external/leveldb.git/+log/ffabb1ae86cc..3dc9202f78a3

$ git log ffabb1ae8..3dc9202f7 --date=short --no-merges --format='%ad %ae %s'
2019-04-23 no-reply [leveldb] Specifically export the WriteBatch::Handler inner class for Windows link
2019-04-15 cmumford Check for possibly invalid offset in test.
2019-04-13 cmumford Changed Windows specific highlighting from bash to cmd.
2019-04-12 cmumford Initialize class members to default values in constructors.

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

Change-Id: I28ed8e909a29212465eab115a9617d9a5c5047bf
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1578596
Auto-Submit: Victor Costan <pwnall@chromium.org>
Reviewed-by: Daniel Murphy <dmurph@chromium.org>
Commit-Queue: Daniel Murphy <dmurph@chromium.org>
Commit-Queue: Victor Costan <pwnall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#653389}

DEPS

@@ -1027,7 +1027,7 @@ deps = {
   },
 
   'src/third_party/leveldatabase/src':
-    Var('chromium_git') + '/external/leveldb.git' + '@' + 'ffabb1ae86cc4eb4516a7c0824c878c3b2d19e5d',
+    Var('chromium_git') + '/external/leveldb.git' + '@' + '3dc9202f78a3eb30ee8c0267e4e4be2e3f986e45',
 
   'src/third_party/libFuzzer/src':
     Var('chromium_git') + '/chromium/llvm-project/compiler-rt/lib/fuzzer.git' + '@' +  Var('libfuzzer_revision'),