Honor the Disable Visual Editor setting (#12000)

* Do not override user_can_richedit option

* Add checks for user_can_richedit() to show plain-text editor

Honors the user setting for `Disable the visual editor when writing`

If the user checks the option to disable visual editor:
- Returns from Gutenberg init
- Removes the links to Classic Editor in post list
- Removes the Gutenberg menu item

When editing a post, it will load the plain text editor.

* Update user_can_richedit added to filter

Moves the user_can_richedit to attach just on the filters
and not spread through out different fucntions.

add_filter( 'gutenberg_can_edit_post_type', 'user_can_richedit', 5 );
add_filter( 'gutenberg_can_edit_post', 'user_can_richedit', 5 );
add_filter( 'use_block_editor_for_post', 'user_can_richedit', 5 );

* Update with just plugin changes

* Don't include core function use_block_editor_for_post

* Don't show Gutenberg menu in admin sidebar, since Demo link will
not load block editor, still plain text editor

* Fix comment

gutenberg.php

@@ -67,6 +67,9 @@ function the_gutenberg_project() {
  * @since 0.1.0
  */
 function gutenberg_menu() {
+	if ( ! gutenberg_can_edit_post( $post ) ) {
+		return;
+	}
 	global $submenu;
 
 	add_menu_page(
@@ -200,6 +203,13 @@ function gutenberg_pre_init() {
 	add_filter( 'replace_editor', 'gutenberg_init', 10, 2 );
 }
 
+/**
+ * Enable Gutenberg based on user_can_richedit setting.
+ * Set gutenberg_can_edit_post based on user setting for disable visual editor.
+ */
+add_filter( 'gutenberg_can_edit_post_type', 'user_can_richedit', 5 );
+add_filter( 'gutenberg_can_edit_post', 'user_can_richedit', 5 );
+
 /**
  * Initialize Gutenberg.
  *

lib/client-assets.php

@@ -1020,12 +1020,6 @@ function gutenberg_editor_scripts_and_styles( $hook ) {
 		'after'
 	);
 
-	// Ignore Classic Editor's `rich_editing` user option, aka "Disable visual
-	// editor". Forcing this to be true guarantees that TinyMCE and its plugins
-	// are available in Gutenberg. Fixes
-	// https://github.com/WordPress/gutenberg/issues/5667.
-	add_filter( 'user_can_richedit', '__return_true' );
-
 	wp_enqueue_script( 'wp-edit-post' );
 	wp_enqueue_script( 'wp-format-library' );
 	wp_enqueue_style( 'wp-format-library' );