Fix bug in split touches.

Cherry-picked down to master.

Change-Id: I786761bd6aecc021ae22d8c9a022324f3a9980d1
diff --git a/libs/ui/InputDispatcher.cpp b/libs/ui/InputDispatcher.cpp
index 8db8c42..16ce24b 100644
--- a/libs/ui/InputDispatcher.cpp
+++ b/libs/ui/InputDispatcher.cpp
@@ -1070,7 +1070,8 @@
         }
 
         // Figure out whether splitting will be allowed for this window.
-        if (newTouchedWindow->layoutParamsFlags & InputWindow::FLAG_SPLIT_TOUCH) {
+        if (newTouchedWindow
+                && (newTouchedWindow->layoutParamsFlags & InputWindow::FLAG_SPLIT_TOUCH)) {
             // New window supports splitting.
             isSplit = true;
         } else if (isSplit) {