Make IME extensions decide when to show the keyboard.

ash/common/system/chromeos/ime_menu/ime_menu_tray.cc

Index: ash/common/system/chromeos/ime_menu/ime_menu_tray.cc
diff --git a/ash/common/system/chromeos/ime_menu/ime_menu_tray.cc b/ash/common/system/chromeos/ime_menu/ime_menu_tray.cc
index 2fd3d3f74625a7ff65c66fd7f1dc518d52bc18c6..13c4dae5a215db9343d985e28121a96649ce3420 100644
--- a/ash/common/system/chromeos/ime_menu/ime_menu_tray.cc
+++ b/ash/common/system/chromeos/ime_menu/ime_menu_tray.cc
@@ -433,7 +433,12 @@ void ImeMenuTray::ShowKeyboardWithKeyset(const std::string& keyset) {
   show_keyboard_ = true;
   if (keyboard_controller) {
     keyboard_controller->AddObserver(this);
-    keyboard_controller->ShowKeyboard(false);
+    // If the keyboard hasn't been loaded yet, it means it's the first time to
+    // show keyboard, OS need to trigger it. Otherwise, make IME extensions

[Shu Chen, 2016/12/26 02:16:39]

// If the keyboard window hasn't been created yet, it means the extension cannot
receive anything to show the keyboard. Therefore, instead of relying the
extension to show the keyboard, forcibly show the keyboard window here (which
will cause the keyboard window created).

[Azure Wei, 2016/12/26 06:53:30]

Done.

+    // decide when to show the keyboard.
+    if (!keyboard_controller->KeyboardHasBeenLoaded()) {

[Shu Chen, 2016/12/26 02:16:39]

s/KeyboardHasBeenLoaded/IsKeyboardWindowCreated/g

[Azure Wei, 2016/12/26 06:53:30]

Done.

+      keyboard_controller->ShowKeyboard(false);
+    }
     return;
   }