Two issues with options in Settings / Manage Search Engines

[lukemulks]

Description

Observing two separate issues, both within the Settings / Manage Search Engines page.

Issue 1: Options available within Default search engines

• I'm not seeing DuckDuckGo listed among the Default Search Engine option.
• It would be ideal if DDG could be placed toward the top of the list of Default Search Engines.
• It would also be good if Qwant, and other privacy-oriented search engine options could be featured in the default search engine list.
• The work for this ^ might already be taking place (I suspect so); flagging as we've made the public announcement of the dev channel build availability, and DDG is a publicly known partner.

Issue 2: Unexpected options under Other search engines

• Some of the options I see under Other search engines seem unexpected.
• For example: Github, Google Drive, Infura Blog, KTLA, Socialblade, Twitter
• The other search engines appear to be related to browsing history, but I wouldn't typically expect any of the examples above to display under search engine settings.
• Each of the examples listed have search querying available within their domains, but wouldn't typically qualify as search engines at the browser level.

Steps to Reproduce

1. Enter: chrome://settings/searchEngines

Actual result:

Expected result:

• Brave search engine partners listed among Default search engine options (search engines we've formed structured partnerships with).
• Other search engine options include search engines submitted from contributors via github.

Reproduces how often:

Easily reproduced

Brave version (about:brave info)

Brave | 0.55.2 Chromium: 70.0.3528.4 (Official Build) dev (64-bit)
-- | --
Revision | 1911f781145b803e04f2d0b5b1a0146ae69fcbdc-refs/branch-heads/3528@{#9}
OS | Windows
JavaScript | V8 7.0.242
Flash | (Disabled)
User Agent | Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3528.4 Safari/537.36

Reproducible on current release:

Website problems only:

• Does the issue resolve itself when disabling Brave Shields?
• Is the issue reproducible on the latest version of Chrome?

Additional Information

[lukemulks]

cc: @bsclifton (ddg/partner optics - not sure who would be best to assign, but suspect you know) ;-)

[bbondy]

I don't think the 2nd thing is an issue, anything that supports open search xml will show up in that list if you hit the site. I think we should add DDG to the list though. Note that people can still configure it, but I think we should just make it easier.

[rebron]

I think the issue is anything that supports open search xml will show up on that list, a list the user doesn't know about or can't clear all at once or as part of clear browsing data. Separate priority from the first issue though.

[bsclifton]

Closing as a duplicate of #731