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

ui/keyboard/keyboard_controller.cc

Index: ui/keyboard/keyboard_controller.cc
diff --git a/ui/keyboard/keyboard_controller.cc b/ui/keyboard/keyboard_controller.cc
index 313bc04f0cd77a1df96babfe2e17b852f3f513d2..08427a0e898ec554d4bcda6584f1a4f3096a8f94 100644
--- a/ui/keyboard/keyboard_controller.cc
+++ b/ui/keyboard/keyboard_controller.cc
@@ -5,6 +5,7 @@
 #include "ui/keyboard/keyboard_controller.h"
 
 #include "base/bind.h"
+#include "base/command_line.h"
 #include "ui/aura/layout_manager.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_delegate.h"
@@ -18,6 +19,7 @@
 #include "ui/gfx/skia_util.h"
 #include "ui/keyboard/keyboard_controller_observer.h"
 #include "ui/keyboard/keyboard_controller_proxy.h"
+#include "ui/keyboard/keyboard_switches.h"
 #include "ui/keyboard/keyboard_util.h"
 
 namespace {
@@ -125,6 +127,7 @@ KeyboardController::KeyboardController(KeyboardControllerProxy* proxy)
     : proxy_(proxy),
       input_method_(NULL),
       keyboard_visible_(false),
+      command_line_for_testing_(NULL),
       weak_factory_(this) {
   CHECK(proxy);
   input_method_ = proxy_->GetInputMethod();
@@ -188,7 +191,10 @@ void KeyboardController::OnTextInputStateChanged(
   bool should_show = was_showing;
   ui::TextInputType type =
       client ? client->GetTextInputType() : ui::TEXT_INPUT_TYPE_NONE;
-  if (type == ui::TEXT_INPUT_TYPE_NONE) {
+  CommandLine* command_line = command_line_for_testing_ ?
+      command_line_for_testing_ : CommandLine::ForCurrentProcess();
+  if (type == ui::TEXT_INPUT_TYPE_NONE &&
+      !command_line->HasSwitch(switches::kKeyboardUsabilityTest)) {
     should_show = false;
   } else {
     if (container_->children().empty()) {