[CUPS] Only allow set up a printer if manufacturer & model or the PPD file is specified.

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 309 matching lines @@
               on-tap="switchToManualAddDialog_">
             $i18n{manuallyAddPrinterButtonText}
           </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>
       </div>
     </add-printer-dialog>
   </template>
 </dom-module>
 
 <dom-module id="add-printer-configuring-dialog">
@@ skipping 47 matching lines @@
     <!-- Manufacturer and Model Dialog -->
     <template is="dom-if" if="[[showManufacturerDialog_]]" restamp>
       <add-printer-manufacturer-model-dialog new-printer="{{newPrinter}}"
           setup-failed="[[setupFailed]]">
       </add-printer-manufacturer-model-dialog>
     </template>
 
   </template>
   <script src="cups_add_printer_dialog.js"></script>
 </dom-module>