Suppress unnecessary "frame not found" errors.

ConsumerFrameEventHistory only stores 8 frames of history,
but video can queue more than 8 frames, which triggers
some annoying ALOGE messages that aren't really errors.

This patch makes sure to print the error only if the
producer has enabled the frame events, which only happens
with EGL where we won't see more than 3 frames queued.

Test: This only affects error reporting.

Change-Id: I184202a71f5fe29159c148957b92fb2e856bf625
diff --git a/include/gui/FrameTimestamps.h b/include/gui/FrameTimestamps.h
index a1d4e07..8a3fa39 100644
--- a/include/gui/FrameTimestamps.h
+++ b/include/gui/FrameTimestamps.h
@@ -199,6 +199,8 @@
     size_t mCompositionOffset{0};
     size_t mRetireOffset{0};
     size_t mReleaseOffset{0};
+
+    bool mProducerWantsEvents{false};
 };