Fix off-device regression test build

Bug: 8093623
Change-Id: I775a8691bbedf58caef07d0b4af59c7444dd81be
diff --git a/java/src/com/android/inputmethod/keyboard/KeyboardLayoutSet.java b/java/src/com/android/inputmethod/keyboard/KeyboardLayoutSet.java
index f28bc94..fd9edec 100644
--- a/java/src/com/android/inputmethod/keyboard/KeyboardLayoutSet.java
+++ b/java/src/com/android/inputmethod/keyboard/KeyboardLayoutSet.java
@@ -32,7 +32,6 @@
 import android.util.Log;
 import android.util.SparseArray;
 import android.util.Xml;
-import android.view.ViewDebug.HierarchyTraceType;
 import android.view.inputmethod.EditorInfo;
 import android.view.inputmethod.InputMethodSubtype;