Fix backing view height calculation in landscape orientation

This logic has been dropped by Ib814c07f.

Bug: 6610497
Change-Id: Id89ad3280b73a31d8c9c6826e9ee297791624db1
diff --git a/java/src/com/android/inputmethod/latin/LatinIME.java b/java/src/com/android/inputmethod/latin/LatinIME.java
index bee374b..ea2746d 100644
--- a/java/src/com/android/inputmethod/latin/LatinIME.java
+++ b/java/src/com/android/inputmethod/latin/LatinIME.java
@@ -969,7 +969,9 @@
         final KeyboardView inputView = mKeyboardSwitcher.getKeyboardView();
         if (inputView == null || mSuggestionsContainer == null)
             return;
-        final int backingHeight = getAdjustedBackingViewHeight();
+        final int adjustedBackingHeight = getAdjustedBackingViewHeight();
+        final boolean backingGone = (mKeyPreviewBackingView.getVisibility() == View.GONE);
+        final int backingHeight = backingGone ? 0 : adjustedBackingHeight;
         // In fullscreen mode, the height of the extract area managed by InputMethodService should
         // be considered.
         // See {@link android.inputmethodservice.InputMethodService#onComputeInsets}.