Block shelf auto hidden when opt-in IME menu is shown.

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 a4542807b7c5283bda602694df1e9955eb762b65..2d2e42928ea76be6d32de9f3e4000d18f6a15a70 100644
--- a/ash/common/system/chromeos/ime_menu/ime_menu_tray.cc
+++ b/ash/common/system/chromeos/ime_menu/ime_menu_tray.cc
@@ -8,6 +8,7 @@
 #include "ash/common/ash_constants.h"
 #include "ash/common/material_design/material_design_controller.h"
 #include "ash/common/session/session_state_delegate.h"
+#include "ash/common/shelf/wm_shelf.h"
 #include "ash/common/shelf/wm_shelf_util.h"
 #include "ash/common/shell_window_ids.h"
 #include "ash/common/system/chromeos/ime_menu/ime_list_view.h"
@@ -277,7 +278,8 @@ ImeMenuTray::ImeMenuTray(WmShelf* wm_shelf)
     : TrayBackgroundView(wm_shelf),
       label_(new ImeMenuLabel()),
       show_keyboard_(false),
-      force_show_keyboard_(false) {
+      force_show_keyboard_(false),
+      should_block_shelf_auto_hide_(false) {
   SetupLabelForTray(label_);
   tray_container()->AddChildView(label_);
   SetContentsBackground();
@@ -351,12 +353,14 @@ void ImeMenuTray::ShowImeMenuBubble() {
 
   bubble_.reset(new TrayBubbleWrapper(this, bubble_view));
   SetDrawBackgroundAsActive(true);
+  should_block_shelf_auto_hide_ = true;
 }
 
 void ImeMenuTray::HideImeMenuBubble() {
   bubble_.reset();
   ime_list_view_ = nullptr;
   SetDrawBackgroundAsActive(false);
+  should_block_shelf_auto_hide_ = false;
 }
 
 bool ImeMenuTray::IsImeMenuBubbleShown() {
@@ -397,6 +401,10 @@ void ImeMenuTray::ShowKeyboardWithKeyset(const std::string& keyset) {
   }
 }
 
+bool ImeMenuTray::ShouldBlockShelfAutoHide() const {
+  return should_block_shelf_auto_hide_;
+}
+
 void ImeMenuTray::SetShelfAlignment(ShelfAlignment alignment) {
   TrayBackgroundView::SetShelfAlignment(alignment);
   if (!MaterialDesignController::IsShelfMaterial())