Cache frame event history producer-side.

* Producer maintains a recent history of frames.
* Producer only does a binder call if requested
    informatiVon doesn't exist in the cache.
* Consumer sends fences to the producer, which
    can be queried for timestamps without a
    binder call.

Test: adb shell /data/nativetest/libgui_test/libgui_test
--gtest_filter=*GetFrameTimestamps*

Change-Id: I8a64579407cc2935f5c659462cb227b07ba27e43
diff --git a/services/surfaceflinger/MonitoredProducer.h b/services/surfaceflinger/MonitoredProducer.h
index 5a2351f..3e64cae 100644
--- a/services/surfaceflinger/MonitoredProducer.h
+++ b/services/surfaceflinger/MonitoredProducer.h
@@ -63,8 +63,7 @@
     virtual IBinder* onAsBinder();
     virtual status_t setSharedBufferMode(bool sharedBufferMode) override;
     virtual status_t setAutoRefresh(bool autoRefresh) override;
-    virtual bool getFrameTimestamps(uint64_t frameNumber,
-            FrameTimestamps* outTimestamps) override;
+    virtual void getFrameTimestamps(FrameEventHistoryDelta *outDelta) override;
     virtual status_t getUniqueId(uint64_t* outId) const override;
 
 private: