Update onboarding flow (brave://welcome)

[bsclifton]

Description

Original description:

We've talked about adjusting the order of the onboarding for Desktop- possibly updating how search looks and where it's placed (currently 4th screen). I believe it was proposed to be the 2nd screen and we may show icons for the options

Once we have a mock up, we can start work to adjust this flow 😄

Per @kjozwiak 's feedback, this is the user-facing issue related to https://github.com/brave/security/issues/216.

Design

The welcome experience must incorporate a new slide that presents the antifraud referral confirmation checkbox to the user:

P3A needed for both checkboxes.

To integrate this slide, improved ordering and visuals should be made to the welcome experience:

• Replace 1st "Let's Go" slide with the import slide
• Search engine slide is 2nd
• Incorporate search engine icons into SE dropdown
• Brave Shields is 3rd
• Antifraud referral confirmation checkbox is 4th
• Brave Rewards is 5th and last
• Update search engine slide graphic
• Update Brave Rewards slide graphic with Lottie file

Assets

Figma: https://www.figma.com/file/MFHpcXJMg2RUQpUJMAZZ4R/?node-id=1159%3A24270

Brave Rewards slide Lottie file:
preview: https://lottiefiles.com/share/6RkxWM
json file: https://assets3.lottiefiles.com/packages/lf20_6RkxWM.json
implementation info: http://airbnb.io/lottie/#/web

[karenkliu]

This is a dupe of this issue: https://github.com/brave/security/issues/216

[kjozwiak]

We'll need a user facing issue that refers to https://github.com/brave/security/issues/216 so it doesn't get lost when QA starts running through verifications. Unless we're planning on moving the work that's being done in https://github.com/brave/security/issues/216 into https://github.com/brave/brave-browser when ready, we should make sure we have a public issue that points to the above so it doesn't get missed by QA.

[karenkliu]

Closing this in favor of these issues:

• MacOS first launch: Set default browser first_run dialog on macOS and Linux #12679
• Windows first launch: Reduce length of welcome experience #12680