Remove synchronization from getCurrentInputMethodSubtype()

getCurrentInputMethodSubtype() acquires InputManagerService.mMethodMap
within its body. There seems to be no reason for holding
InputMethodManager.mH to call getCurrentInputMethodSubtype(). Holding mH
can cause potential deadlock b/w two threads acquiring mH and mMethodMap
in different orders.

Bug: 31247871
Bug: 31273203
Bug: b.android.com/218423
Change-Id: I20cf2c20f49b1b02c0f7a18257b49d4bcc081b5d

1 files changed, 4 insertions, 6 deletions

diff --git a/core/java/android/view/inputmethod/InputMethodManager.java b/core/java/android/view/inputmethod/InputMethodManager.java
index 4013b30fce06..0b7ac88c6925 100644
--- a/core/java/android/view/inputmethod/InputMethodManager.java
+++ b/core/java/android/view/inputmethod/InputMethodManager.java
@@ -2053,12 +2053,10 @@ public final class InputMethodManager {
      * have any input method subtype.
      */
     public InputMethodSubtype getCurrentInputMethodSubtype() {
-        synchronized (mH) {
-            try {
-                return mService.getCurrentInputMethodSubtype();
-            } catch (RemoteException e) {
-                throw e.rethrowFromSystemServer();
-            }
+        try {
+            return mService.getCurrentInputMethodSubtype();
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
         }
     }