This update adds styles and theme support related to the new block-based editor to enhance the experience of using it with Twenty Seventeen.
These are the specific changes made to this theme:
* Add blocks.css, to style blocks on the front end, to make sure they match the theme’s existing HTML element styles.
* Add editor-blocks.css to style blocks in the editor, to make sure they match the theme’s existing HTML element styles.
* Add theme support for `editor-styles`, to pull the existing editor stylesheet into the new editor.
* Add theme support for `wp-block-styles`, to load the default block styles on the front end.
Props laurelfulford, ianbelanger, crunnells.
Fixes#45045.
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