Move checkoutHeadRevision to Workspace.

src/register-default-commands.coffee

@@ -204,7 +204,7 @@ module.exports = ({commandRegistry, commandInstaller, config, notificationManage
     'editor:newline-below': -> @insertNewlineBelow()
     'editor:newline-above': -> @insertNewlineAbove()
     'editor:toggle-line-comments': -> @toggleLineCommentsInSelection()
-    'editor:checkout-head-revision': -> @checkoutHeadRevision()
+    'editor:checkout-head-revision': -> atom.workspace.checkoutHeadRevision(this)
     'editor:move-line-up': -> @moveLineUp()
     'editor:move-line-down': -> @moveLineDown()
     'editor:move-selection-left': -> @moveSelectionLeft()

src/text-editor.coffee

@@ -712,25 +712,6 @@ class TextEditor extends Model
   # via {Pane::saveItemAs}.
   getSaveDialogOptions: -> {}
 
-  checkoutHeadRevision: ->
-    if @getPath()
-      checkoutHead = =>
-        @project.repositoryForDirectory(new Directory(@getDirectoryPath()))
-          .then (repository) =>
-            repository?.async.checkoutHeadForEditor(this)
-
-      if @config.get('editor.confirmCheckoutHeadRevision')
-        @applicationDelegate.confirm
-          message: 'Confirm Checkout HEAD Revision'
-          detailedMessage: "Are you sure you want to discard all changes to \"#{@getFileName()}\" since the last Git commit?"
-          buttons:
-            OK: checkoutHead
-            Cancel: null
-      else
-        checkoutHead()
-    else
-      Promise.resolve(false)
-
   ###
   Section: Reading Text
   ###

src/workspace.coffee

@@ -1085,3 +1085,22 @@ class Workspace extends Model
 
       inProcessFinished = true
       checkFinished()
+
+  checkoutHeadRevision: (editor) ->
+    if editor.getPath()
+      checkoutHead = =>
+        @project.repositoryForDirectory(new Directory(editor.getDirectoryPath()))
+          .then (repository) =>
+            repository?.async.checkoutHeadForEditor(editor)
+
+      if @config.get('editor.confirmCheckoutHeadRevision')
+        @applicationDelegate.confirm
+          message: 'Confirm Checkout HEAD Revision'
+          detailedMessage: "Are you sure you want to discard all changes to \"#{editor.getFileName()}\" since the last Git commit?"
+          buttons:
+            OK: checkoutHead
+            Cancel: null
+      else
+        checkoutHead()
+    else
+      Promise.resolve(false)