SF: Adding dynamic switching between 30 and 60 Hz in Scheduler.

Turn on frame skipping when 30Hz.
Record FPS in systrace: 24, 30, 60.

Results from paying youtube app:
file:///Users/akrulec/Desktop/scheduler_24_fps_trace.html
file:///Users/akrulec/Desktop/scheduler_30_fps_trace.html
file:///Users/akrulec/Desktop/scheduler_60_fps_trace.html

see go/surface-flinger-scheduler for more info.

Test: SF tests pass.
Change-Id: Ief8efbd5f16a74ed8f84906cb341a368118423a7
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 4c3be4d..dfe05ab 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -1245,6 +1245,10 @@
 
     if (makeAvailable) {
         mHWVsyncAvailable = true;
+        // TODO(b/113612090): This is silly, but necessary evil until we turn on the flag for good.
+        if (mUseScheduler) {
+            mScheduler->makeHWSyncAvailable(true);
+        }
     } else if (!mHWVsyncAvailable) {
         // Hardware vsync is not currently available, so abort the resync
         // attempt for now