RecentlyClosedBridge lets caller choose number of tabs to return.

This enables clients of RecentlyClosedBridge to request a specific
number of recently closed tabs.

BUG=308820
NOTRY=true

Review URL: https://codereview.chromium.org/77133003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@236433 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 236433