Migrate IDisplayEventConnection interface to AIDL

This addresses security vulnerabilities due to hard coded binder
interface.

Bug: 195660647
Test: atest services/surfaceflinger/tests/unittests/SchedulerTest.cpp
Change-Id: I948e97e37056286d54623ca6232580187b138e62
diff --git a/services/surfaceflinger/Scheduler/EventThread.cpp b/services/surfaceflinger/Scheduler/EventThread.cpp
index 455289f..627c49a 100644
--- a/services/surfaceflinger/Scheduler/EventThread.cpp
+++ b/services/surfaceflinger/Scheduler/EventThread.cpp
@@ -170,20 +170,21 @@
     mEventThread->registerDisplayEventConnection(this);
 }
 
-status_t EventThreadConnection::stealReceiveChannel(gui::BitTube* outChannel) {
+binder::Status EventThreadConnection::stealReceiveChannel(gui::BitTube* outChannel) {
     outChannel->setReceiveFd(mChannel.moveReceiveFd());
     outChannel->setSendFd(base::unique_fd(dup(mChannel.getSendFd())));
-    return NO_ERROR;
+    return binder::Status::ok();
 }
 
-status_t EventThreadConnection::setVsyncRate(uint32_t rate) {
-    mEventThread->setVsyncRate(rate, this);
-    return NO_ERROR;
+binder::Status EventThreadConnection::setVsyncRate(int rate) {
+    mEventThread->setVsyncRate(static_cast<uint32_t>(rate), this);
+    return binder::Status::ok();
 }
 
-void EventThreadConnection::requestNextVsync() {
+binder::Status EventThreadConnection::requestNextVsync() {
     ATRACE_NAME("requestNextVsync");
     mEventThread->requestNextVsync(this);
+    return binder::Status::ok();
 }
 
 status_t EventThreadConnection::postEvent(const DisplayEventReceiver::Event& event) {