Remove updatedCupsPrintersUiEnabled

- This is the first part of removing legacy printer settings code.
- Future CL's will iteratively remove each piece of the feature flag and
  the code gated by it.

Bug: 1005905
Test: Ran browsertests + end to end manual
Change-Id: I4e4680e7eb2dcd08d03f69538fc09331b3f39a64
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1935152Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Reviewed-by: Bailey Berro <baileyberro@chromium.org>
Commit-Queue: jimmy gong <jimmyxgong@chromium.org>
Cr-Commit-Position: refs/heads/master@{#722523}

chrome/browser/resources/settings/printing_page/cups_printers.js

@@ -66,7 +66,7 @@ Polymer({
     enableUpdatedUi_: {
       type: Boolean,
       value: function() {
-        return loadTimeData.getBoolean('updatedCupsPrintersUiEnabled');
+        return true;
       },
     },
 

chrome/browser/ui/webui/settings/settings_localized_strings_provider.cc

@@ -2527,10 +2527,6 @@ void AddPrintingStrings(content::WebUIDataSource* html_source) {
   html_source->AddString(
       "printingCUPSPrintPpdLearnMoreUrl",
       GetHelpUrlWithBoard(chrome::kCupsPrintPPDLearnMoreURL));
-
-  html_source->AddBoolean(
-      "updatedCupsPrintersUiEnabled",
-      base::FeatureList::IsEnabled(features::kCupsPrintersUiOverhaul));
 #endif
 }
 

chrome/test/data/webui/settings/chromeos/cups_printer_page_tests.js

@@ -116,6 +116,8 @@ suite('CupsAddPrinterDialogTests', function() {
 
     PolymerTest.clearBody();
     page = document.createElement('settings-cups-printers');
+    // TODO(jimmyxgong): Remove this line when the feature flag is removed.
+    page.enableUpdatedUi_ = false;
     document.body.appendChild(page);
     assertTrue(!!page);
     dialog = page.$$('settings-cups-add-printer-dialog');