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

content/common/view_messages.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // IPC messages for page rendering.
 // Multiply-included message file, hence no include guard.
 
 #include "base/memory/shared_memory.h"
 #include "base/process/process.h"
 #include "base/strings/string16.h"
@@ skipping 1084 matching lines @@
 //   Indicates if an input method is active in the browser process.
 //   The possible actions when a renderer process receives this message are
 //   listed below:
 //     Value Action
 //     true  Start sending IPC message ViewHostMsg_ImeUpdateTextInputState
 //           to notify the input method status of the focused edit control.
 //     false Stop sending IPC message ViewHostMsg_ImeUpdateTextInputState.
 IPC_MESSAGE_ROUTED1(ViewMsg_SetInputMethodActive,
                     bool /* is_active */)
 
+// IME API oncandidatewindow* events for InputMethodContext.
+IPC_MESSAGE_ROUTED0(ViewMsg_CandidateWindowShow)
+IPC_MESSAGE_ROUTED0(ViewMsg_CandidateWindowUpdate)
+IPC_MESSAGE_ROUTED0(ViewMsg_CandidateWindowHide)
+
 // This message sends a string being composed with an input method.
 IPC_MESSAGE_ROUTED4(
     ViewMsg_ImeSetComposition,
     string16, /* text */
     std::vector<blink::WebCompositionUnderline>, /* underlines */
     int, /* selectiont_start */
     int /* selection_end */)
 
 // This message confirms an ongoing composition.
 IPC_MESSAGE_ROUTED3(ViewMsg_ImeConfirmComposition,
@@ skipping 1262 matching lines @@
 // synchronously (see crbug.com/120597). This IPC message sends the character
 // bounds after every composition change to always have correct bound info.
 IPC_MESSAGE_ROUTED2(ViewHostMsg_ImeCompositionRangeChanged,
                     gfx::Range /* composition range */,
                     std::vector<gfx::Rect> /* character bounds */)
 #endif
 
 // Adding a new message? Stick to the sort order above: first platform
 // independent ViewMsg, then ifdefs for platform specific ViewMsg, then platform
 // independent ViewHostMsg, then ifdefs for platform specific ViewHostMsg.