Enable Native CUPS printing on Chrome OS.

chrome/browser/chromeos/printer_detector/printer_detector_factory.cc

Index: chrome/browser/chromeos/printer_detector/printer_detector_factory.cc
diff --git a/chrome/browser/chromeos/printer_detector/printer_detector_factory.cc b/chrome/browser/chromeos/printer_detector/printer_detector_factory.cc
index 4008a07eb05ef8f68f83a4f985d69b458ebf62f1..c50216e475998297e2bad6256bac04653590bf5d 100644
--- a/chrome/browser/chromeos/printer_detector/printer_detector_factory.cc
+++ b/chrome/browser/chromeos/printer_detector/printer_detector_factory.cc
@@ -45,8 +45,8 @@ PrinterDetectorFactory::~PrinterDetectorFactory() {
 
 KeyedService* PrinterDetectorFactory::BuildServiceInstanceFor(
     content::BrowserContext* context) const {
-  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
-          ::switches::kEnableNativeCups)) {
+  if (!base::CommandLine::ForCurrentProcess()->HasSwitch(
+          ::switches::kDisableNativeCups)) {
     return PrinterDetector::CreateCups(Profile::FromBrowserContext(context))

[Carlson, 2017/03/31 21:45:52]

Probably slightly better to flip the contents of the if and else blocks here
instead of inverting the condition.  if (!disabled) is a quasi-double-negative.

[skau, 2017/03/31 23:29:09]

Done.

         .release();
   } else {