[NgOptimizedImage] Revert Assertions Against Blob and Data URL's or Document the Rationale

[paulyy-y]

Which @angular/* package(s) are relevant/related to the feature request?

common

Description

Commit 801daf8 added assertions against using blob: and data: URL's. for NgOptimizedImage.

I cannot find any reasoning provided in either the documentation for the NgOptimizedImage directive 1 2 nor in the source changes. The documentation makes it seem like 'ngSrc' is a drop-in-replacement for the src attribute with no warning or indication that there are significant regressions in functionality when using it as such. Note: IDE's such as JetBrains Webstorm actively lint against using src and suggest replacing it with ngSrc in Angular projects.

Removing these assertions shows expected behavior without any issues. So why was this introduced? Maybe there is a great reason for these changes... the commit description provides 0 insight and the error message asking users to simply stop using it is not a fantastic UX.

Proposed solution

Revert the commit and allow those inputs. Happy to do a PR but would like confirmation that there isn't some special reasons for this constraint first.

Alternatives considered

Add documentation to:

1. The directive documentation outlining there are clear caveats and regressions going from ngSrc to src.
2. The source logic indicating why these assertions are needed (a simple one liner like // These types conflict with Foo logic, so we prevent them from being used helps posterity tremendously).

[rudyhadoux]

Hi, AWS Amplify uses S3 pre-signed image URLs.
Why it is rejected as invalid value ?