Block Editor: check style-editor-rtl.css in RTL languages

[mostafa.s1990]

Keep in mind that all our themes don't have the style-editor-rtl.css file! Because the new version gives the following error.

PHP Warning: file_get_contents(beta/wp-content/themes/twentynineteen/style-editor-rtl.css): failed to open stream: No such file or directory in beta\wp-admin\edit-form-blocks.php on line 204

[youknowriad]

Do you have an exemple of theme causing this, to check properly? as the logic seems to apply only when there's a defined editor style. And also the editor styles is opt-in, so this won't break any existing them unless they opt-in.

[youknowriad]

I'm punting this for now. We can reconsider if we have more information.

[youknowriad]

Moving back to 5.0.0 as it seems it happens in all themes with Gutenberg support in RTL languages.

[youknowriad]

Patch was valid thanks @mostafa.s1990 I updated it with a slightly simpler version. Should be good to go.

[youknowriad]

I created this Gutenberg issue to backport it into the plugin ​https://github.com/WordPress/gutenberg/issues/12196

[matveb]

Looks good.

[youknowriad]

In 43923:

Block Editor: Fix PHP warning showing up when loading editor styles while in RTL.

In RTL languages, WordPress adds style-editor-rtl.css editor styles to the global $editor_styles
This patch ignores handling these styles if the file is not preset.

Props desrosj, mostafa.s1990.
Fixes #45288.

[desrosj]

In 44270:

Block Editor: Fix PHP warning when loading editor styles while in RTL.

In RTL languages, WordPress adds style-editor-rtl.css editor styles to the global $editor_styles.
This patch ignores handling these styles if the file is not preset.

Also, clarify the docs for the return value of the block_version function.

Props mostafa.s1990, desrosj, mukesh27.

Merges [43923] and [43924] to trunk.

Fixes #45288, #45342.