Enable Config::MUS to use classic IME instead of servicified IME.

ui/aura/mus/window_tree_host_mus.cc

Index: ui/aura/mus/window_tree_host_mus.cc
diff --git a/ui/aura/mus/window_tree_host_mus.cc b/ui/aura/mus/window_tree_host_mus.cc
index 2c6f3b2dd4321994dd07a7f0c902d7e939ed1945..2e7f9e5da536278203ed14d70f9340ffc29ffea3 100644
--- a/ui/aura/mus/window_tree_host_mus.cc
+++ b/ui/aura/mus/window_tree_host_mus.cc
@@ -19,6 +19,10 @@
 #include "ui/events/event.h"
 #include "ui/platform_window/stub/stub_window.h"
 
+#if defined(OS_CHROMEOS)
+#include "ui/base/ime/input_method_chromeos.h"
+#endif
+
 DECLARE_UI_CLASS_PROPERTY_TYPE(aura::WindowTreeHostMus*);
 
 namespace aura {
@@ -80,10 +84,7 @@ WindowTreeHostMus::WindowTreeHostMus(WindowTreeHostMusInitParams init_params)
   SetPlatformWindow(
       base::MakeUnique<ui::StubWindow>(this, use_default_accelerated_widget));
 
-  input_method_ = base::MakeUnique<InputMethodMus>(this, window());
-  input_method_->Init(init_params.window_tree_client->connector());
-  SetSharedInputMethod(input_method_.get());
-
+  InitInputMethod(&init_params);
   compositor()->SetHostHasTransparentBackground(true);
 
   // Mus windows are assumed hidden.
@@ -119,6 +120,19 @@ void WindowTreeHostMus::SetBoundsFromServer(const gfx::Rect& bounds_in_pixels) {
   SetBoundsInPixels(bounds_in_pixels);
 }
 
+void WindowTreeHostMus::DispatchEventToInputMethod(
+    ui::KeyEvent* event,
+    std::unique_ptr<base::Callback<void(bool)>> ack_callback) {
+#if defined(OS_CHROMEOS)
+  if (input_method_chromeos_) {
+    input_method_chromeos_->DispatchKeyEvent(event, std::move(ack_callback));
+    return;
+  }
+#endif
+  DCHECK(input_method_mus_);
+  input_method_mus_->DispatchKeyEvent(event, std::move(ack_callback));
+}
+
 void WindowTreeHostMus::SetClientArea(
     const gfx::Insets& insets,
     const std::vector<gfx::Rect>& additional_client_area) {
@@ -209,4 +223,19 @@ void WindowTreeHostMus::MoveCursorToScreenLocationInPixels(
   Env::GetInstance()->set_last_mouse_location(location_in_pixels);
 }
 
+void WindowTreeHostMus::InitInputMethod(
+    WindowTreeHostMusInitParams* init_params) {
+#if defined(OS_CHROMEOS)
+  if (init_params->use_classic_ime) {
+    input_method_chromeos_ = base::MakeUnique<ui::InputMethodChromeOS>(this);

[sky, 2017/04/20 20:18:49]

Are you sure we need to set the input method at all in classic? We will soon be
using this code:
https://chromium.googlesource.com/chromium/src/+/master/ash/display/window_tr...
which sets the SharedInputMethod.

+    SetSharedInputMethod(input_method_chromeos_.get());
+    return;
+  }
+#endif  // defined(OS_CHROMEOS)
+
+  input_method_mus_ = base::MakeUnique<InputMethodMus>(this, window());
+  input_method_mus_->Init(init_params->window_tree_client->connector());
+  SetSharedInputMethod(input_method_mus_.get());
+}
+
 }  // namespace aura