IME for Mus: Make InputMethodMus use the IME Mojo API.

mash/session/session.cc

Index: mash/session/session.cc
diff --git a/mash/session/session.cc b/mash/session/session.cc
index ff3753606d5111d3037afc00f6b15ad4721faeda..1c0e3761f5637fbe6eb42818307fd8d137ad9d25 100644
--- a/mash/session/session.cc
+++ b/mash/session/session.cc
@@ -31,6 +31,7 @@ void Session::OnStart(const shell::Identity& identity) {
   StartAppDriver();
   StartWindowManager();
   StartQuickLaunch();
+  StartIMEDriver();
   // Launch a chrome window for dev convience; don't do this in the long term.
   connector()->Connect("exe:chrome");
 }
@@ -109,6 +110,12 @@ void Session::StartQuickLaunch() {
                  base::Unretained(this)));
 }
 
+void Session::StartIMEDriver() {
+  StartRestartableService(
+      "mojo:test_ime_driver",
+      base::Bind(&Session::StartIMEDriver, base::Unretained(this)));
+}
+
 void Session::StartScreenlock() {
   StartRestartableService(
       "mojo:screenlock",