[Magnifier-26] Wire up frame callback for realsies

Test: none yet
Bug: 73810478
Bug: 72041926
Change-Id: I7154ed4b3d2cd820dc8c8ff55eed130be87d1606

libs/hwui/renderthread/DrawFrameTask.cpp

@@ -94,12 +94,20 @@ void DrawFrameTask::run() {
 
     // Grab a copy of everything we need
     CanvasContext* context = mContext;
+    std::function<void(int64_t)> callback = std::move(mFrameCallback);
 
     // From this point on anything in "this" is *UNSAFE TO ACCESS*
     if (canUnblockUiThread) {
         unblockUiThread();
     }
 
+    // Even if we aren't drawing this vsync pulse the next frame number will still be accurate
+    if (CC_UNLIKELY(callback)) {
+        context->enqueueFrameWork([callback, frameNr = context->getFrameNumber()]() {
+            callback(frameNr);
+        });
+    }
+
     if (CC_LIKELY(canDrawThisFrame)) {
         context->draw();
     } else {