Implements a display scale tray setting behind a chrome switch

chrome/browser/about_flags.cc

Index: chrome/browser/about_flags.cc
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index 6b4eb075fd465f7cc3d3c8c908874982f32810d9..8f71c43b2190ec21ab6a667ad68f139f304b88c8 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -2844,6 +2844,13 @@ const FeatureEntry kFeatureEntries[] = {
      flag_descriptions::kLocationHardReloadDescription, kOsAll,
      FEATURE_VALUE_TYPE(features::kLocationHardReload)},
 
+#if defined(USE_ASH) && defined(OS_CHROMEOS)
+    {"ash-enable-scale-settings-tray",
+     flag_descriptions::kAshEnableScaleSettingsTrayName,
+     flag_descriptions::kAshEnableScaleSettingsTrayDescription, kOsCrOS,
+     SINGLE_VALUE_TYPE(ash::switches::kAshEnableScaleSettingsTray)},
+#endif

[oshima, 2017/05/06 19:50:22]

I prefer not to expose this to users.
Rather we should hook up with the UI scale.

+
     // NOTE: Adding new command-line switches requires adding corresponding
     // entries to enum "LoginCustomFlags" in histograms/enums.xml. See note in
     // enums.xml and don't forget to run AboutFlagsHistogramTest unit test.