Remove style-editor-title.css once Gutenberg specificity issues are fixed

[nickcernis]

Gutenberg functionality was merged in #121 in a single folder at lib/gutenberg.

Currently, editor styles for the post title live in their own file at lib/gutenberg/style-editor-title.css due to specificity issues with Gutenberg editor styles that prevent the post title being styled via style-editor.css.

This issue is a reminder to adapt and move those styles into lib/gutenberg/style-editor.css once these issues in Gutenberg are resolved (hopefully before WP 5.0 lands):

• Add support for page title styles within editor-styles.  WordPress/gutenberg#10485
• Editor stylesheet CSS specificity issues WordPress/gutenberg#10067

The title styling currently looks like this:

.editor-post-title__block .editor-post-title__input {
    font-family: 'Source Sans Pro', sans-serif;
    font-size: 30px;
    font-weight: 400;
    line-height: 1.2;
    margin: 0 0 20px;
}

It will need to be changed to this and be moved to style-editor.css once the above issues are solved:

body .editor-post-title__block .editor-post-title__input {
    font-family: 'Source Sans Pro', sans-serif;
    font-size: 30px;
    font-weight: 400;
    line-height: 1.2;
    margin: 0 0 20px;
}

The extra admin stylesheet at lib/gutenberg/style-editor-title.css can then be removed and the require line removed from lib/gutenberg/init.php.

This code in style-editor.css will also need to change once the above issues are resolved:

body[data-align="wide"] {
	max-width: 1092px !important;
}

body[data-align="full"] {
	max-width: none !important;
}

The upcoming proposal to handle wide and full block widths looks like this instead:

.wp-block[data-align="wide"] {
	max-width: 1092px;
}

.wp-block[data-align="full"] {
	max-width: none;
}

[nickcernis]

Completed work on updating Gutenberg editor stylesheet for WP 5.0 Beta 3 / Gutenberg 4.2 changes:

• 02b4c52

• a88383a

• 5258048