Make virtual keyboard work on supervised user creation

ash/test/ash_test_base.cc

Index: ash/test/ash_test_base.cc
diff --git a/ash/test/ash_test_base.cc b/ash/test/ash_test_base.cc
index 1de82986a3aba0df5d9f74e83dd8e73b565b685e..56249a8218c210f7192cbdc3f530e53d513e16c3 100644
--- a/ash/test/ash_test_base.cc
+++ b/ash/test/ash_test_base.cc
@@ -48,6 +48,7 @@
 #include "ui/display/types/display_constants.h"
 #include "ui/events/gesture_detection/gesture_configuration.h"
 #include "ui/gfx/geometry/point.h"
+#include "ui/keyboard/keyboard_controller.h"
 #include "ui/wm/core/coordinate_conversion.h"
 
 #if defined(USE_X11)
@@ -169,6 +170,14 @@ void AshTestBase::SetUp() {
 
   ash_test_helper_->SetUp(start_session_);
 
+  // The following function should be invoked from
+  // ChromeBrowserMainExtraPartsAsh::PostProfileInit
+  // on real Chrome OS. Without this,
+  // LockActionHandlerLayoutManagerTest.KeyboardBounds fails on
+  // ShowKeyboard(true).
+  ash::Shell::GetPrimaryRootWindowController()->ActivateKeyboard(
+      keyboard::KeyboardController::GetInstance());

[xiyuan, 2017/06/07 15:08:13]

If only that test fails without this, should this be part of that test's SetUp
instead?

ash_test_helper_->SetUp() call above should set ACTIVE session state and
CreateKeyboard should be exercised. Not sure why we need to do this now.

[oka, 2017/06/07 15:45:19]

ash_test_helper_->SetUp() initializes the keyboard controller instance from
RootWindowController::Init(), before the state becomes active. The same thing
happens on real OS on start up.
However, on real workflow, RootWindowController::ActivateKeyboard is called
after that from ChromeBrowserMainExtraPartsAsh::PostProfileInit and the
controller  becomes a sane state.

[xiyuan, 2017/06/07 16:18:13]

But Shell::CreateKeyboard calls ActivateKeyboard too. So if session state
changes to ACTIVE, Shell::CreateKeyboard should do that already. I don't
understand why we need to do this explicitlyl again here.

+
   Shell::GetPrimaryRootWindow()->Show();
   Shell::GetPrimaryRootWindow()->GetHost()->Show();
   // Move the mouse cursor to far away so that native events doesn't