Fix "Unknown app_id" issue by resend "forwardGetListing"

[nghiadhd]

I fixed "Unknown app_id" issue by

Keep the app_id of "Safari"
Resend "forwardGetListing" with app_id of "Safari" if we meet "Unknown app_id"
I tested with 6 iOS devices (from 9.0.1 to 9.3.4) run in parallel with Appium

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[nghiadhd]

I signed it!

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CLAs look good, thanks!

[artygus]

@nghiadhd thanks for contribution!