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..83e770f0d2a0880d6caf07d2a0746661a0bbbbed 100644
--- a/ash/common/system/chromeos/ime_menu/ime_menu_tray.cc
+++ b/ash/common/system/chromeos/ime_menu/ime_menu_tray.cc
@@ -362,6 +362,11 @@ ImeMenuTray::~ImeMenuTray() {
   SystemTrayNotifier* tray_notifier = WmShell::Get()->system_tray_notifier();
   tray_notifier->RemoveIMEObserver(this);
   tray_notifier->RemoveVirtualKeyboardObserver(this);
+  keyboard::KeyboardController* keyboard_controller =
+      keyboard::KeyboardController::GetInstance();
+  if (keyboard_controller) {
+    keyboard_controller->RemoveObserver(this);
+  }
 }
 
 void ImeMenuTray::ShowImeMenuBubble() {
@@ -433,7 +438,13 @@ void ImeMenuTray::ShowKeyboardWithKeyset(const std::string& keyset) {
   show_keyboard_ = true;
   if (keyboard_controller) {
     keyboard_controller->AddObserver(this);
-    keyboard_controller->ShowKeyboard(false);
+    // 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).

[bshe, 2016/12/29 19:22:15]

The comment here is not very clear. It looks like you prevent showing keyboard
on native side if keyboard window is already created. I am assuming this is
because you want extension to call private api to show keyboard so you skip it
here. Perhaps reword your comment here.

[Azure Wei, 2017/01/03 03:37:40]

Updated the comment here.

+    if (!keyboard_controller->IsKeyboardWindowCreated()) {
+      keyboard_controller->ShowKeyboard(false);
+    }
     return;
   }
 
@@ -549,6 +560,11 @@ void ImeMenuTray::OnKeyboardBoundsChanging(const gfx::Rect& new_bounds) {}
 void ImeMenuTray::OnKeyboardClosed() {
   if (InputMethodManager::Get())
     InputMethodManager::Get()->OverrideKeyboardUrlRef(std::string());
+  keyboard::KeyboardController* keyboard_controller =
+      keyboard::KeyboardController::GetInstance();
+  if (keyboard_controller)
+    keyboard_controller->RemoveObserver(this);
+
   show_keyboard_ = false;
   force_show_keyboard_ = false;
 }