[PRImpl] Move JourneyLogger into ComponentPRImpl

Change:
* Move JourneyLogger into ComponentPRImpl to facilitate the moving of
PRImpl#close() into ComponentPRImpl.
* Move the PRImpl.Delegate.isOffTheRecord interface method into
PRFactory. The value of isOffTheRecord will be set according to the
merchant page's state at PRFactory#createImpl().

Bug: 1102522

Change-Id: I46de04bdde95e48d8ecdf1c31cf2685fef213001
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2341948
Commit-Queue: Liquan (Max) Gu <maxlg@chromium.org>
Reviewed-by: Rouslan Solomakhin <rouslan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#796473}