* For #5334: added private custom tab processor
* For #5334 - Fixes up IntentReceiverActivity for handling intents
* For 5334: update styling for private custom tabbs
* For 5334: update tests to account for new processors
Note that two are still failing. These appear to be true failures, and will be corrected in a later commit.
* For 5334: fixes bug introduced by changes to IntentReceiverActivity
RCA: intent className and extra were previously set based on which processors matched, not which successfully processed. This patch reintroduces that behavior.
* For 5334: add tests for custom tabs processing
As an added bonus, this makes the temporal coupling between `setPrivateModeIfNecessary` and `setupThemeAndBrowsingMode` explicit. They previously would have broken if called in reverse order, now it will fail to compile.
Severin Rudie