Include InputMethodSubtypeSwitchingController in state dump.

In order to diagnose IME issues in multi-user / multi-profile
environment, internal state of
InputMethodSubtypeSwitchingController needs to be included in
the bugreport.

Bug: 19340792
Bug: 19587437
Bug: 21612582
Change-Id: I34aca2c1a4330ec08b5e40441e631809a8bb844e
diff --git a/services/core/java/com/android/server/InputMethodManagerService.java b/services/core/java/com/android/server/InputMethodManagerService.java
index e099297..0513d8b 100644
--- a/services/core/java/com/android/server/InputMethodManagerService.java
+++ b/services/core/java/com/android/server/InputMethodManagerService.java
@@ -3713,6 +3713,8 @@
             p.println("  mCurUserActionNotificationSequenceNumber="
                     + mCurUserActionNotificationSequenceNumber);
             p.println("  mSystemReady=" + mSystemReady + " mInteractive=" + mScreenOn);
+            p.println("  mSwitchingController:");
+            mSwitchingController.dump(p);
         }
 
         p.println(" ");