Logs stack trace when IME doesn't get attached when all apps swipes up

Bug: 178904132
Test: Manual

Change-Id: I3b62a1a8e927ca8bac4db07053f781260fbff515
diff --git a/src/com/android/launcher3/allapps/AllAppsInsetTransitionController.java b/src/com/android/launcher3/allapps/AllAppsInsetTransitionController.java
index 1cf98e1..f6e54aa 100644
--- a/src/com/android/launcher3/allapps/AllAppsInsetTransitionController.java
+++ b/src/com/android/launcher3/allapps/AllAppsInsetTransitionController.java
@@ -164,8 +164,11 @@
                     @Override
                     public void onCancelled(@Nullable WindowInsetsAnimationController controller) {
                         if (DEBUG) {
-                            Log.d(TAG, "Listener.onCancelled ctrl=" + controller
-                                    + " mAnimationController=" + mAnimationController);
+                            // Keep the verbose logging to chase down IME not showing up issue.
+                            // b/178904132
+                            Log.e(TAG, "Listener.onCancelled ctrl=" + controller
+                                    + " mAnimationController=" + mAnimationController,
+                                    new Exception());
                         }
                         if (mState == State.DRAG_START_BOTTOM) {
                             mState = State.DRAG_START_BOTTOM_IME_CANCELLED;