Add --keyboard-usability-test flag and always show keyboard unless manually hide

chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.cc

Index: chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.cc
diff --git a/chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.cc b/chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.cc
index a4ad3490aa44bb4a8e642bb12d8a2df788cad584..b4ba426002dcd683e14ccc482fd04e635591e2a1 100644
--- a/chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.cc
+++ b/chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.h"
 
+#include "ash/root_window_controller.h"
 #include "ash/session_state_delegate.h"
 #include "ash/shell.h"
 #include "base/command_line.h"
@@ -88,9 +89,14 @@ void ChromeBrowserMainExtraPartsAsh::PreProfileInit() {
 }
 
 void ChromeBrowserMainExtraPartsAsh::PostProfileInit() {
-  // Initialize TabScrubber after the Ash Shell has been initialized.
-  if (ash::Shell::HasInstance())
+  // Initialize TabScrubber and activate keyboard after the Ash Shell has been
+  // initialized.
+  if (ash::Shell::HasInstance()) {
     TabScrubber::GetInstance();
+    // Virtual keyboard depends on the default profile.
+    ash::Shell::GetPrimaryRootWindowController()->ActivateKeyboard(
+        ash::Shell::GetInstance()->keyboard_controller());
+  }
 }
 
 void ChromeBrowserMainExtraPartsAsh::PostMainMessageLoopRun() {