Revert of chromeos: Remove some IME methods from ash::SystemTrayDelegate

ash/accelerators/accelerator_controller.h

Index: ash/accelerators/accelerator_controller.h
diff --git a/ash/accelerators/accelerator_controller.h b/ash/accelerators/accelerator_controller.h
index 9cc79cc43ec52885d11baa332b302d7444eaa34d..f982495964fe7ec9a28129cb8c68ee8488a32b98 100644
--- a/ash/accelerators/accelerator_controller.h
+++ b/ash/accelerators/accelerator_controller.h
@@ -33,6 +33,7 @@
 struct AcceleratorData;
 class AcceleratorControllerDelegate;
 class ExitWarningHandler;
+class ImeControlDelegate;
 
 // AcceleratorController provides functions for registering or unregistering
 // global keyboard accelerators, which are handled earlier than any windows. It
@@ -107,6 +108,9 @@
   // Returns the restriction for the current context.
   AcceleratorProcessingRestriction GetCurrentAcceleratorRestriction();
 
+  void SetImeControlDelegate(
+      std::unique_ptr<ImeControlDelegate> ime_control_delegate);
+
   // Provides access to the ExitWarningHandler for testing.
   ExitWarningHandler* GetExitWarningHandlerForTest() {
     return &exit_warning_handler_;
@@ -182,6 +186,8 @@
 
   // A tracker for the current and previous accelerators.
   std::unique_ptr<ui::AcceleratorHistory> accelerator_history_;
+
+  std::unique_ptr<ImeControlDelegate> ime_control_delegate_;
 
   // Handles the exit accelerator which requires a double press to exit and
   // shows a popup with an explanation.