Fixed crash when user tries to install ipfs extension from setting

[simonhong]

When extension install is requested, install dialog is launched.
So far, we requested un-parented install dialog.
On linux, custom frame is not allowed for un-parented dialog.
Only platform-native frame is used for it. The problem was
install dialog tries to set title to custom frame. So, seg fault
happened only on linux. And Windows with classic theme will have
same issue. On macOS and Windows with aero, crash doesn't happen.
But, un-parented dialog on macOS has title area that looks ugly.

Resolves brave/brave-browser#9092
Resolves brave/brave-browser#7325

Linux:

MacOS (parented dialog)

MacOS (previously used one - un parented dialog)

Submitter Checklist:

• Submitted a ticket for my issue if one did not already exist.
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).
• Verified that these changes build without errors on
  • Android
  • iOS
  • Linux
  • macOS
  • Windows
• Verified that these changes pass automated tests (unit, browser, security tests) on
  • iOS
  • Linux
  • macOS
  • Windows
• Verified that all lint errors/warnings are resolved (npm run lint)
• Ran git rebase master (if needed).
• Ran git rebase -i to squash commits (if needed).
• Tagged reviewers and labelled the pull request as needed.
• Request a security/privacy review as needed.
• Add appropriate QA labels (QA/Yes or QA/No) to include the closed issue in milestone
• Public documentation has been updated as necessary. For instance:
  • https://github.com/brave/brave-browser/wiki/Deviations-from-Chromium-(features-we-disable-or-remove)
  • https://github.com/brave/brave-browser/wiki/Proxy-redirected-URLs
  • https://github.com/brave/brave-browser/wiki/Fingerprinting-Protections
  • https://github.com/brave/brave-browser/wiki/Brave%E2%80%99s-Use-of-Referral-Codes
  • https://github.com/brave/brave-browser/wiki/Custom-Headers
  • https://github.com/brave/brave-browser/wiki/Web-compatibility-issues-with-tracking-protection
  • https://github.com/brave/brave-browser/wiki/QA-Guide

Test Plan:

1. Launch browser and open settings
2. Toggle ipfs extensions on

Reviewer Checklist:

• New files have MPL-2.0 license header.
• Request a security/privacy review as needed.
• Adequate test coverage exists to prevent regressions
• Verify test plan is specified in PR before merging to source

After-merge Checklist:

• The associated issue milestone is set to the smallest version that the
  changes has landed on.
• All relevant documentation has been updated.

[yrliou]

LGTM

[kjozwiak]

Verification PASSED on both macOS 10.15.3 x64 & Ubuntu 19.10 x64 using the following builds:

Brave | 1.9.21 Chromium: 81.0.4044.92 (Official Build) nightly (64-bit)
--- | ---
Revision | 32921c79b6f01a0fb2deef0e1d45b42f96581051-refs/branch-heads/4044@{#883}
OS | macOS Version 10.15.3 (Build 19D76)

Brave | 1.9.21 Chromium: 81.0.4044.92 (Official Build) nightly (64-bit)
--- | ---
Revision | 32921c79b6f01a0fb2deef0e1d45b42f96581051-refs/branch-heads/4044@{#883}
OS | Linux

• ensured that enabling IPFS Companion via brave://settings/extensions doesn't crash Brave
• ensured that the IPFS Companion modals match the examples under Fixed crash when user tries to install ipfs extension from setting #5205 (comment) when enabling IPFS Companion
• ensured that enabling IPFS Companion opens chrome-extension://nibjojkomfdiaoajekhjakgkdhaomnch/dist/landing-pages/welcome/index.html`
• ensured that you can disable/enable IPFS Companion via brave://settings/extensions without any issues
• ensured that the Extension: IPFS Companion process starts under Task Manager when enabling IPFS Companion
• ensured that the Extension: IPFS Companion process closes under Task Manager when disabling IPFS Companion
• ensured that clicking on the IPFS Companion extension icon worked without any issues

Examples:

[bbondy]

Thanks @simonhong 👍