Do not use default setting when value is false

[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).

fix #4903

Auditors: @bbondy

Test Plan:

1. Turn on/off "Always show the URL bar" in about:preferences#general
2. The title mode should work as expected

[bsclifton]

++ (and my bad on introducing this- doh)

[bbondy]

++ thanks!