Return the transform to apply in getLastQueuedBuffer

Bug: 28428955
Change-Id: Id48f7d3bf3f5deb074cf0a6a52a41caac875db41
diff --git a/include/gui/IGraphicBufferProducer.h b/include/gui/IGraphicBufferProducer.h
index 049406c..37ae6df 100644
--- a/include/gui/IGraphicBufferProducer.h
+++ b/include/gui/IGraphicBufferProducer.h
@@ -563,9 +563,11 @@
     // the queue, outBuffer will be populated with nullptr and outFence will be
     // populated with Fence::NO_FENCE
     //
+    // outTransformMatrix is not modified if outBuffer is null.
+    //
     // Returns NO_ERROR or the status of the Binder transaction
     virtual status_t getLastQueuedBuffer(sp<GraphicBuffer>* outBuffer,
-            sp<Fence>* outFence) = 0;
+            sp<Fence>* outFence, float outTransformMatrix[16]) = 0;
 };
 
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