Do not use RefBase in EventHub

Switch to std::unique_ptr instead.
Unfortunately, have to also switch to shared_ptr because FakeEventHub
implements EventHub but is also used to inject events when testing
InputReader.

Bug: 117684064
Test: atest inputflinger_tests
Change-Id: I789ba0ca255b6a1f179711c61fc9da98a3c6a800
diff --git a/services/inputflinger/InputReaderFactory.cpp b/services/inputflinger/InputReaderFactory.cpp
index 3534f6b..072499b 100644
--- a/services/inputflinger/InputReaderFactory.cpp
+++ b/services/inputflinger/InputReaderFactory.cpp
@@ -22,7 +22,7 @@
 sp<InputReaderInterface> createInputReader(
         const sp<InputReaderPolicyInterface>& policy,
         const sp<InputListenerInterface>& listener) {
-    return new InputReader(new EventHub(), policy, listener);
+    return new InputReader(std::make_unique<EventHub>(), policy, listener);
 }
 
 } // namespace android
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