Disable Quick View by default and add about flag to enable it.

chromeos/chromeos_switches.cc

Index: chromeos/chromeos_switches.cc
diff --git a/chromeos/chromeos_switches.cc b/chromeos/chromeos_switches.cc
index d063dce7a2f9226533d1f91e01b77a603d1fe061..5d4c3eb8e836f2f50e10782ae7f94fe1da6551ed 100644
--- a/chromeos/chromeos_switches.cc
+++ b/chromeos/chromeos_switches.cc
@@ -86,7 +86,7 @@ const char kDisableCloudImport[] = "disable-cloud-import";
 // Disables the ChromeOS demo.
 const char kDisableDemoMode[] = "disable-demo-mode";
 
-// Disable quick view in Files app.
+// Disables quick view in Files app.
 const char kDisableFilesQuickView[] = "disable-files-quick-view";
 
 // Disable HID-detection OOBE screen.
@@ -140,6 +140,9 @@ const char kEnableConsumerManagement[] = "enable-consumer-management";
 // Enables details panel in Files app.
 const char kEnableFilesDetailsPanel[] = "enable-files-details-panel";
 
+// Enables quick view in Files app.
+const char kEnableFilesQuickView[] = "enable-files-quick-view";
+
 // Disables notification when device is in end of life status.
 const char kDisableEolNotification[] = "disable-eol-notification";