get_block_wrapper_attributes checks for outdated __experimentalColor support

[noisysocks]

Copied from ​https://github.com/WordPress/gutenberg/issues/27670.

Describe the bug
Serverside rendered blocks with support for colors do not generate the appropriate classes if colors are set.

To reproduce
Steps to reproduce the behavior:

1. Create any block with server side rendering, add support for color in its metadata.
2. Use get_block_wrapper_attributes in the render callback.
3. Check generated classes/styles

Expected behavior
Appropriate classes/styles should be generated.

Reason
wp_apply_colors_support checks for __experimentalColor instead of color when determining block support for color. See here: ​https://github.com/WordPress/WordPress/blob/master/wp-includes/block-supports/colors.php#L66
The classes get generated correctly if I add the __experimentalColor flag additonally in my block.json file.

"supports": {
  "color": true
}

Above does not work, below works.

"supports": {
  "color": true,
  "__experimentalColor": true
}

Editor version (please complete the following information):

• WordPress version: 5.6
• Does the website has Gutenberg plugin installed, or is it using the block editor that comes by default? "default"
• If the Gutenberg plugin is installed, which version is it? [e.g., 7.6]

Fixes ​https://github.com/WordPress/gutenberg/issues/27670 (see the issue for details)

Props to ​https://github.com/rafhun

https://core.trac.wordpress.org/ticket/52709

[noisysocks]

I'll commit this since I and @youknowriad have reviewed it.

Thanks @nosolosw!

[noisysocks]

In 50488:

Block Editor: Fix color support for dynamic blocks

Changes wp_apply_colors_support to check for for color instead of
experimentalColor when determining block support for color.

Props nosolosw, rafhun, youknowriad.
See #52709.

[noisysocks]

In 50489:

Block Editor: Fix color support for dynamic blocks

Changes wp_apply_colors_support to check for for color instead of
experimentalColor when determining block support for color.

Props nosolosw, rafhun, youknowriad.
See #52709.