tree ca0a3a3e74a0bfb376338202b64d291b9e45020d
parent 4d9729ee13a58103814ecdddb485d413c44ee052
author Nelly Vouzoukidou <nellyv@google.com> 1544003506 +0100
committer CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org> 1544210634 +0000

[ledger] Don't wait on LevelDb initialization for page-usage db.

Bug: LE-652 #done

PageEvictionManagerImpl initialization (and consequently
DiskCleanupManager initialization) is no longer blocked on
initializing the required LevelDb instance. To do this, page usage
db is now getting the LevelDb instance throught LevelDbFactory, which
uses the I/O thread for creating it.

This CL also implements GetIteratorAtPrefix in FakeDb and uses FakeDb
on disk_cleanup_manager_unittest and page_eviction_manager_impl_unittest.

Test: Existing test still pass.
      Modular integration tests are no longer flaky on the qemu bots

Change-Id: Ic7df8e62a310f23500bc1a9c1b9640c17ec25f5e