SF: Hook up VSYNC injection to Scheduler

This CL refactors VSYNC injection to interface with the Scheduler API,
and removes otherwise unused EventThread members.

Bug: 128863962
Test: sffakehwc_test
Change-Id: I2ba143bb78baf3e66a47b90163eacf0d0e431124
diff --git a/services/surfaceflinger/Scheduler/DispSyncSource.h b/services/surfaceflinger/Scheduler/DispSyncSource.h
index 740c8c4..536464e 100644
--- a/services/surfaceflinger/Scheduler/DispSyncSource.h
+++ b/services/surfaceflinger/Scheduler/DispSyncSource.h
@@ -32,6 +32,7 @@
     ~DispSyncSource() override = default;
 
     // The following methods are implementation of VSyncSource.
+    const char* getName() const override { return mName; }
     void setVSyncEnabled(bool enable) override;
     void setCallback(VSyncSource::Callback* callback) override;
     void setPhaseOffset(nsecs_t phaseOffset) override;