Revert "SF: pass a render rate to VsyncTracker instead of a divisor"

Revert submission 21422016

Reason for revert: DM P0 (b/269561042)

Reverted changes: /q/submissionid:21422016

Bug: 269561042
Change-Id: I118dd75ea379673d649d3c75960f18ef45b3749f
(cherry picked from commit 3d21d3afa1056efacf702b74449f9e2e7b5701f1)
Merged-In: I118dd75ea379673d649d3c75960f18ef45b3749f
diff --git a/services/surfaceflinger/Scheduler/VSyncTracker.h b/services/surfaceflinger/Scheduler/VSyncTracker.h
index bc0e3bc..8d1629f 100644
--- a/services/surfaceflinger/Scheduler/VSyncTracker.h
+++ b/services/surfaceflinger/Scheduler/VSyncTracker.h
@@ -80,16 +80,15 @@
     virtual bool isVSyncInPhase(nsecs_t timePoint, Fps frameRate) const = 0;
 
     /*
-     * Sets a render rate on the tracker. If the render rate is not a divisor
-     * of the period, the render rate is ignored until the period changes.
+     * Sets a divisor on the rate (which is a multiplier of the period).
      * The tracker will continue to track the vsync timeline and expect it
      * to match the current period, however, nextAnticipatedVSyncTimeFrom will
-     * return vsyncs according to the render rate set. Setting a render rate is useful
+     * return vsyncs according to the divisor set. Setting a divisor is useful
      * when a display is running at 120Hz but the render frame rate is 60Hz.
      *
-     * \param [in] Fps   The render rate the tracker should operate at.
+     * \param [in] divisor   The rate divisor the tracker should operate at.
      */
-    virtual void setRenderRate(Fps) = 0;
+    virtual void setDivisor(unsigned divisor) = 0;
 
     virtual void dump(std::string& result) const = 0;