UI Unresponsive in #630 & #634

[danishjafri88]

Description:

In #630 & #634 The UI became unresponsive when tab tray controller was tapped (or keyboard shortcut was used) after the STR in those issues. There is a inherent issue in the code to show tab tray, which blocks UI.

Steps to Reproduce

1. Follow STR in Command+T keyboard shortcut with private browsing on freezes browser #634 or Private Browsing Leaking History when using "Open in Brave" #630
2. Tap on tab tray button / Press command+T

Actual result:
Unresponsive UI(This may not be reproducible as the fixes for above issues avoids this problem.)

Expected result:
Tab tray is shown.

Reproduces how often: [Easily reproduced, Intermittent Issue]

Brave Version:

Device details:

Website problems only:

• did you check with Brave Shields down?
• did you check in Safari/Firefox (WkWebView-based browsers)?

Additional Information

[srirambv]

Verified on iPhone 7+ and iPad Pro. No UI freeze

[srirambv]

• Verification passed on iPhone 7 running 1.9.2(19.5.8.23)
• Verification passed on iPhone 8 running 1.9.2(19.5.8.23)
• Verified passed with iPad 5th Gen running 1.9.2(19.5.8.23) - followed STR from Private Browsing Leaking History when using "Open in Brave" #630 and then steps in description. Unable to test with steps from Command+T keyboard shortcut with private browsing on freezes browser #634 as I don't have an external keyboard for my iPad.
• Verification passed on iPhone SE running 1.9.2(19.5.8.23)
• Verification passed on iPad Mini 4 using iOS 12.2 running 1.9.2(19.5.8.23)