Don't show animation of content setting image at all

[simonhong]

Frequent slide animation distracts users.

Fix brave/brave-browser#3751

Submitter Checklist:

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  • https://github.com/brave/brave-browser/wiki/Fingerprinting-Protection-Mode
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Test Plan:

See brave/brave-browser#3751 for STR.

Reviewer Checklist:

• New files have MPL-2.0 license header.
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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.

[darkdh]

we can get rid of the entire autoplay animation by removing this line

brave-core/browser/ui/content_settings/brave_autoplay_blocked_image_model.cc

Line 35 in 8cf2416

set_explanatory_string_id(IDS_BLOCKED_AUTOPLAY_TITLE);

Widevine used to have this animation and it is removed
so why do we still show it for the first time if user find it annoying?

[bsclifton]

Asking for designer/pm input now... cc: @bradleyrichter @rebron

[simonhong]

@darkdh Yup, we can hide with empty explanatory string for autoplay.
This PR is more general fix for disabling all slide animation not just for autoplay. (waiting for @rebron 's more inputs about this.)

[rebron]

I discussed with @bradleyrichter. Let's remove slide animation altogether, don't even show for first time use.

[simonhong]

@darkdh slide animations for all content settings are disabled. PTAL again.

[bsclifton]

Awesome job on this one, @simonhong! Thanks for the quick review, @darkdh 😄

[the-4-limbos]

Is it normal that i am still getting the auto video play is blocked 'notification' in my adress bar?

Brave is up to date
Version 0.66.99 Chromium: 75.0.3770.100 (Official Build) (64-bit)

It show it to me every time i go to another page on facebook

[simonhong]

@the-4-limbos yes, this change is not yet in current stable(0.66). It is int dev channel (0.68.x)