[FYI] All-in-one OnCandidateWindow{Show,Update,Hide}

ui/base/ime/input_method_imm32.cc

Index: ui/base/ime/input_method_imm32.cc
diff --git a/ui/base/ime/input_method_imm32.cc b/ui/base/ime/input_method_imm32.cc
index 074f37cd9ac6ae738861ca79f52f53987ec73f6d..7cb28f491264560b9490155c856298e0473551e2 100644
--- a/ui/base/ime/input_method_imm32.cc
+++ b/ui/base/ime/input_method_imm32.cc
@@ -238,9 +238,17 @@ LRESULT InputMethodIMM32::OnImeNotify(UINT message,
   switch (wparam) {
   case IMN_OPENCANDIDATE:
     is_candidate_popup_open_ = true;
+    NotifyCandidateWindowStateChanged();

[yukawa, 2013/11/25 05:07:42]

I'm not sure if we can safely call back external code from here.  Using PostTask
to avoid nested message handler might be safer.  Please note that objects that
implement TextInputClient can do anything (e.g., calling
InputMehotd::CancelComposition) at this line.

     break;
   case IMN_CLOSECANDIDATE:
     is_candidate_popup_open_ = false;
+    NotifyCandidateWindowStateChanged();
+    break;
+  case IMN_CHANGECANDIDATE:
+    // TODO(kochi): The IME API expects this event to notify window size change,
+    // while this may fire more often without window resize. There is no generic

[yukawa, 2013/11/25 05:07:42]

"There is no generic way to get bounds of candidate window."
I haven't investigated yet but we might be able to use IMC_GETCANDIDATEPOS
request. If this is true, we might want to
say "Not all IMEs support IMC_GETCANDIDATEPOS request."

+    // way to get bounds of candidate window.
+    NotifyCandidateWindowStateChanged();
     break;
   }