Keep a backward compatible DOM structure for atom-text-editor contents

src/off-screen-block-decorations-component.js

@@ -6,6 +6,7 @@ module.exports = class OffScreenBlockDecorationsComponent {
     this.oldState = {offScreenBlockDecorations: {}, width: 0}
     this.domNode = document.createElement('div')
     this.domNode.style.visibility = 'hidden'
+    this.domNode.style.position = 'absolute'
     this.blockDecorationNodesById = {}
   }
 

src/text-editor-component.coffee

@@ -62,11 +62,7 @@ class TextEditorComponent
 
     @domElementPool = new DOMElementPool
     @domNode = document.createElement('div')
-    @domNode.classList.add('editor-contents')
-    # TODO: Remove these backwards compatible classes once everyone has
-    # transitioned to non-shadow DOM selectors.
     @domNode.classList.add('editor-contents--private')
-    @domNode.classList.add('editor--private')
 
     @overlayManager = new OverlayManager(@presenter, @domNode, @views)
 

src/text-editor-element.coffee

@@ -30,7 +30,18 @@ class TextEditorElement extends HTMLElement
     @setAttribute('tabindex', -1)
 
   initializeContent: (attributes) ->
-    @rootElement = this
+    Object.defineProperty(this, 'shadowRoot', {
+      get: =>
+        Grim.deprecate("""
+        The contents of `atom-text-editor` elements are no longer encapsulated
+        within a shadow DOM boundary. Please, stop using `shadowRoot` and access
+        the editor contents directly instead.
+        """)
+        this
+    })
+    @rootElement = document.createElement('div')
+    @rootElement.classList.add('editor--private')
+    @appendChild(@rootElement)
 
   attachedCallback: ->
     @buildModel() unless @getModel()?
@@ -106,7 +117,7 @@ class TextEditorElement extends HTMLElement
       workspace: @workspace
       assert: @assert
     )
-    @appendChild(@component.getDomNode())
+    @rootElement.appendChild(@component.getDomNode())
     inputNode = @component.hiddenInputComponent.getDomNode()
     inputNode.addEventListener 'focus', @focused.bind(this)
     inputNode.addEventListener 'blur', => @dispatchEvent(new FocusEvent('blur', bubbles: false))