[leveldb] tracking memory used by in-memory Env's.

leveldb::InMemoryEnv is not exposed with no official support for
calculating memory usage. However, this is a pretty decent estimate
and will be helpful for tracking in-memory Env RAM use.

Bug: 750803
Change-Id: I4e07327bf4480bdb786290c82d8f66412868f36a
Reviewed-on: https://chromium-review.googlesource.com/601207
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Siddhartha S <ssid@chromium.org>
Cr-Commit-Position: refs/heads/master@{#552361}

CrOS-Libchrome-Original-Commit: 8d26d10a0ad0c75d5a96f09f7c5677e51faac230
1 file changed
tree: 8a9c63c77cc95a0bf37ec6ecc7c7f52de272478a
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/