Change the sort ordering for nearby printers

-New sort order is printers with automatic configuration sorted
alphabetically first then printers that need manual configuration
sorted alphabetically next

-Added new test case to confirm nearby printers sorted correctly

Bug: 993820
Change-Id: Idf730c8111bc6e835b659e899e3a478d719e04a8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1767604
Commit-Queue: Gavin Williams <gavinwill@chromium.org>
Reviewed-by: Bailey Berro <baileyberro@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#690885}

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

@@ -15,6 +15,8 @@ let PrinterListEntry;
  * These values correspond to the different types of printers available. Refer
  * to cups_printer_management.md for more information about the different
  * categories of printers.
+ *
+ * The types are numbered in desired sorting order for display.
  */
 const PrinterType = {
   SAVED: 0,

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

@@ -59,15 +59,29 @@ Polymer({
             item =>this.matchesSearchTerm_(item.printerInfo,this.searchTerm)) :
         this.printers.slice();
 
-    updatedPrinters.sort((first, second) => {
-      return settings.printing.alphabeticalSort(
-          first.printerInfo, second.printerInfo);
-    });
+    updatedPrinters.sort(this.sortPrinters_);
 
     this.updateList('filteredPrinters_', printer => printer.printerInfo,
         updatedPrinters);
   },
 
+
+  /**
+   * @param {!PrinterListEntry} first
+   * @param {!PrinterListEntry} second
+   * @return {number}
+   * @private
+   */
+  sortPrinters_: function(first, second) {
+    if (first.printerType == second.printerType) {
+      return settings.printing.alphabeticalSort(
+          first.printerInfo, second.printerInfo);
+    }
+
+    // PrinterType sort order maintained in cups_printer_types.js
+    return first.printerType - second.printerType;
+  },
+
   /**
    * @param {!CupsPrinterInfo} printer
    * @param {string} searchTerm

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

@@ -509,6 +509,53 @@ suite('CupsNearbyPrintersTests', function() {
     });
   });
 
+  test('nearbyPrintersSortOrderAutoFirstThenDiscovered', function() {
+    let discoveredPrinterA =
+        createCupsPrinterInfo('printerNameA', 'printerAddress1', 'printerId1');
+    let discoveredPrinterB =
+        createCupsPrinterInfo('printerNameB', 'printerAddress2', 'printerId2');
+    let discoveredPrinterC =
+        createCupsPrinterInfo('printerNameC', 'printerAddress3', 'printerId3');
+    let autoPrinterD =
+        createCupsPrinterInfo('printerNameD', 'printerAddress4', 'printerId4');
+    let autoPrinterE =
+        createCupsPrinterInfo('printerNameE', 'printerAddress5', 'printerId5');
+    let autoPrinterF =
+        createCupsPrinterInfo('printerNameF', 'printerAddress6', 'printerId6');
+
+    // Add printers in a non-alphabetical order to test sorting.
+    const automaticPrinterList = [autoPrinterF, autoPrinterD, autoPrinterE];
+    const discoveredPrinterList =
+        [discoveredPrinterC, discoveredPrinterA, discoveredPrinterB];
+
+    // Expected sort order is to sort automatic printers first then
+    // sort discovered printers
+    const expectedPrinterList = [
+      autoPrinterD, autoPrinterE, autoPrinterF, discoveredPrinterA,
+      discoveredPrinterB, discoveredPrinterC
+    ];
+
+    return test_util.flushTasks().then(() => {
+      nearbyPrintersElement = page.$$('settings-cups-nearby-printers');
+      assertTrue(!!nearbyPrintersElement);
+
+      // Assert that no printers have been detected.
+      let nearbyPrinterEntries = getPrinterEntries(nearbyPrintersElement);
+      assertEquals(0, nearbyPrinterEntries.length);
+
+      // Simuluate finding nearby printers.
+      cr.webUIListenerCallback(
+          'on-nearby-printers-changed', automaticPrinterList,
+          discoveredPrinterList);
+
+      Polymer.dom.flush();
+
+      nearbyPrinterEntries = getPrinterEntries(nearbyPrintersElement);
+
+      verifyPrintersList(nearbyPrinterEntries, expectedPrinterList);
+    });
+  });
+
   test('addingAutomaticPrinterIsSuccessful', function() {
     const automaticPrinterList = [createCupsPrinterInfo('test1', '1', 'id1')];
     const discoveredPrinterList = [];