[CUPS] Remove the left button in 'manufacturer-and-model' dialog.

chrome/browser/resources/settings/printing_page/cups_add_printer_dialog.html

 <link rel="import" href="chrome://resources/html/md_select_css.html">
 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/html/web_ui_listener_behavior.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-button/paper-button.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-input/paper-input.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-spinner/paper-spinner.html">
 <link rel="import" href="../i18n_setup.html">
 <link rel="import" href="cups_add_printer_dialog_util.html">
 <link rel="import" href="cups_printers_browser_proxy.html">
 <link rel="import" href="../settings_shared_css.html">
@@ skipping 243 matching lines @@
         width: 340px;
       }
 
       .error-message {
         background-color: var(--google-red-100);
         color: red;
         margin-top: 10px;
         padding: 10px 20px;
       }
 
-      .dialog-buttons {
-        display: flex;
-        justify-content: space-between;
-        width: 100%;
-      }
-
       #browseButton {
         color: black;
         font-size: inherit;
       }
     </style>
     <add-printer-dialog>
       <div class="dialog-title">$i18n{addPrintersManuallyTitle}</div>
       <div class="dialog-body">
         <div class="settings-box two-line">
           <div class="start">
@@ skipping 25 matching lines @@
                 </paper-button>
               </paper-input>
             </div>
           </div>
         </div>
         <div class="error-message" hidden="[[!setupFailed]]">
           Driver not found (exact error message TBD)
         </div>
       </div>
       <div class="dialog-buttons">
-        <div>  <!-- Left group -->
-          <paper-button id="manuallyAddPrinterButton" class="secondary-button"
-              on-tap="switchToPreviousDialog_">
-            $i18n{back}
-          </paper-button>
-        </div>
-        <div>  <!-- Right group -->
-          <paper-button class="cancel-button secondary-button"
-              on-tap="onCancelTap_">
-            $i18n{cancelButtonText}
-          </paper-button>
-          <paper-button class="action-button" id="addPrinterButton"
-              disabled="[[!canAddPrinter_(newPrinter.printerManufacturer,
-                                          newPrinter.printerModel,
-                                          newPrinter.printerPPDPath)]]"
-              on-tap="switchToConfiguringDialog_">
-            $i18n{addPrinterButtonText}
-          </paper-button>
-        </div>
+        <paper-button class="cancel-button secondary-button"
+            on-tap="onCancelTap_">
+          $i18n{cancelButtonText}
+        </paper-button>
+        <paper-button class="action-button" id="addPrinterButton"
+            disabled="[[!canAddPrinter_(newPrinter.printerManufacturer,
+                                        newPrinter.printerModel,
+                                        newPrinter.printerPPDPath)]]"
+            on-tap="switchToConfiguringDialog_">
+          $i18n{addPrinterButtonText}
+        </paper-button>
       </div>
     </add-printer-dialog>
   </template>
 </dom-module>
 
 <dom-module id="add-printer-configuring-dialog">
   <template>
     <style include="settings-shared">
       .dialog-body {
         padding-top: 140px;
@@ skipping 36 matching lines @@
     <template is="dom-if" if="[[showConfiguringDialog_]]" restamp>
       <add-printer-configuring-dialog
           printer-name="[[newPrinter.printerName]]"
           dialog-title="[[configuringDialogTitle]]">
       </add-printer-configuring-dialog>
     </template>
 
     <!-- Manufacturer and Model Dialog -->
     <template is="dom-if" if="[[showManufacturerDialog_]]" restamp>
       <add-printer-manufacturer-model-dialog new-printer="{{newPrinter}}"
-          previous-dialog="[[previousDialog]]" setup-failed="[[setupFailed]]">
+          setup-failed="[[setupFailed]]">
       </add-printer-manufacturer-model-dialog>
     </template>
 
   </template>
   <script src="cups_add_printer_dialog.js"></script>
 </dom-module>