Harden construction sites of android::StrongPointer.

Bug: 393217449
Test: presubmit
Flag: EXEMPT_refactor
Change-Id: Icf703aed608531e9b302b299481af00a52074731
diff --git a/libs/gui/DisplayEventDispatcher.cpp b/libs/gui/DisplayEventDispatcher.cpp
index 68f10f4..67ca39c 100644
--- a/libs/gui/DisplayEventDispatcher.cpp
+++ b/libs/gui/DisplayEventDispatcher.cpp
@@ -59,7 +59,8 @@
     }
 
     if (mLooper != nullptr) {
-        int rc = mLooper->addFd(mReceiver.getFd(), 0, Looper::EVENT_INPUT, this, NULL);
+        int rc = mLooper->addFd(mReceiver.getFd(), 0, Looper::EVENT_INPUT,
+                                sp<LooperCallback>::fromExisting(this), NULL);
         if (rc < 0) {
             return UNKNOWN_ERROR;
         }