Remove unused roles(EditableText, SplitGroup, GrowArea) from Chromium.

chrome/browser/resources/chromeos/chromevox/common/chrome_extension_externs.js

Index: chrome/browser/resources/chromeos/chromevox/common/chrome_extension_externs.js
diff --git a/chrome/browser/resources/chromeos/chromevox/common/chrome_extension_externs.js b/chrome/browser/resources/chromeos/chromevox/common/chrome_extension_externs.js
index d4366b7f9a3d07705970c093fcd6bd0426617541..fa859fe7c2034fcbdac367b2ad59db0c385d1ab9 100644
--- a/chrome/browser/resources/chromeos/chromevox/common/chrome_extension_externs.js
+++ b/chrome/browser/resources/chromeos/chromevox/common/chrome_extension_externs.js
@@ -1427,13 +1427,11 @@ chrome.automation.RoleType = {
     disclosureTriangle: 'disclosureTriangle',
     div: 'div',
     document: 'document',
-    editableText: 'editableText',
     embeddedObject: 'embeddedObject',
     footer: 'footer',
     form: 'form',
     grid: 'grid',
     group: 'group',
-    growArea: 'growArea',
     heading: 'heading',
     horizontalRule: 'horizontalRule',
     iframe: 'iframe',
@@ -1441,7 +1439,6 @@ chrome.automation.RoleType = {
     imageMapLink: 'imageMapLink',
     imageMap: 'imageMap',
     image: 'image',
-    incrementor: 'incrementor',
     inlineTextBox: 'inlineTextBox',
     labelText: 'labelText',
     legend: 'legend',
@@ -1487,7 +1484,6 @@ chrome.automation.RoleType = {
     sliderThumb: 'sliderThumb',
     spinButtonPart: 'spinButtonPart',
     spinButton: 'spinButton',
-    splitGroup: 'splitGroup',
     splitter: 'splitter',
     staticText: 'staticText',
     status: 'status',