Revert "Move FlagManager to a common SF lib"

Revert submission 25261159-flagmanager_common

Reason for revert: build breakage: b/310935941

Reverted changes: /q/submissionid:25261159-flagmanager_common

Change-Id: I44795b34c4ef97b78c080d6421eb61a454675ddb
diff --git a/services/surfaceflinger/Scheduler/EventThread.cpp b/services/surfaceflinger/Scheduler/EventThread.cpp
index 693a357..7f627f8 100644
--- a/services/surfaceflinger/Scheduler/EventThread.cpp
+++ b/services/surfaceflinger/Scheduler/EventThread.cpp
@@ -43,9 +43,9 @@
 #include <utils/Errors.h>
 #include <utils/Trace.h>
 
-#include <common/FlagManager.h>
 #include <scheduler/VsyncConfig.h>
 #include "DisplayHardware/DisplayMode.h"
+#include "FlagManager.h"
 #include "FrameTimeline.h"
 #include "VSyncDispatch.h"
 #include "VSyncTracker.h"