Add default lastAccessTime for history entries only

[darkdh]

• Submitted a ticket for my issue if one did not already exist.
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).
• Ran git rebase -i to squash commits (if needed).

Also add creationTime field for future use

fix #5183

Auditors: @bsclifton, @bbondy

Test Plan:

1. Import bookmarks
2. They should not appear in about:history until you visit them

[bbondy]

++

[bsclifton]

++