Clicking "add to metamask" from brave browser on mobile incorrectly shows "added to Metamask"

[sketsdever]

Repro

1. User has Metamask app installed on mobile
2. User has not added Protect before
3. Clicks "add to Metamask" button
4. Bad behavior: Button updates to "added to Metamask"

The correct behavior would be

• Ideally: Initiates flow to add to metamask
• Compromise (what we do with safari): Say 'metamask not detected'

Right now the behavior is just straight misleading though.