Integration of Image and Image2

[Olek Nowodziński]

Following #11201:

• Image and image2 got to share command, button, dialog and other names.
• The "old image" plugin should detect whether image2 is loaded: if so it will stay disabled.

Obstacles:

• The way the image plugin is disabled.
• The dependency between image plugin and "image button" (forms).
• Testing stuff. I.e. it's already been noticed that if a build contains image, image2 and forms, "image button" works fine even though image plugin is not initialized.
• The less people will have troubles because of that change, the better.

[Olek Nowodziński]

Created branch ​t/11222 in dev:

1. Renamed:
   • Dialog
   • Button
   • Context menu
   • CSS classes
   • The widget
   • Icons
   • Helpers
2. Simplified samples (also dev):
   • Removed removePlugins: 'image,forms'
3. Forced "image" plugins and "ImageButton" to turn off when "image2" is detected.

Created branch t/11222 in tests:

1. Aligned "image2" tests to new names.
2. Added dt/plugins/image2/relations.html to make sure 3. from the list above really works.

[Piotrek Koszuliński]

Do we still need this?

	config.filebrowserImage2BrowseUrl = config.filebrowserImageBrowseUrl;
	config.filebrowserImage2UploadUrl = config.filebrowserImageUploadUrl;

[Piotrek Koszuliński]

We decided to revert the name of image2's dialog to image2, so it will be possible to use both plugins on one page with multiple editors.

[Olek Nowodziński]

Replying to Reinmar:

We decided to revert the name of image2's dialog to image2, so it will be possible to use both plugins on one page with multiple editors.

Done. Tests should match.

Also:

• Added a few words of comments to dirty hacks found in the code.
• Slightly simplified some definitions in Image2 dialog.
• Fixed broken dialog tab navigation when Browse button is visible (no one even noticed that...).
• Reverted a dirty, magic numbers-driven hack introduced by #10895 (​https://github.com/ckeditor/ckeditor-dev/commit/d4f479a253#diff-59c209b735207291fc5e470bd14ec2d3R540). Simplified that thing by adding the "Browse" button dynamically instead of re-organizing the existing structure.

[Matti Järvinen]

Depends on #10931 Allow nesting widgets?

[Piotrek Koszuliński]

@matti: Nesting widgets is not a requirement for this ticket. This ticket is mostly about the naming and having the image2 disabling image if both are loaded.

[Piotrek Koszuliński]

I forced pushed branches with one commit removed in each. We cannot rename CKEDITOR.plugins.image2 to image too.

I checked how both plugins work together, on one page and it's ok. Tests for full-all build pass to.

[Olek Nowodziński]

​git:18df3e2 landed in master (dev), 805d7ac (tests).