Plumbing through GPU context priority

TODO: Actually return priority from Render engine, instead of random
number.

Test: Compile and observe logcat.
Bug: 168740533
Change-Id: Id8d93e315162708a2a8afa1e87ebdf97ab53a20f
diff --git a/libs/gui/tests/Surface_test.cpp b/libs/gui/tests/Surface_test.cpp
index ce3afa2..7761db8 100644
--- a/libs/gui/tests/Surface_test.cpp
+++ b/libs/gui/tests/Surface_test.cpp
@@ -887,6 +887,8 @@
         return NO_ERROR;
     }
 
+    int getGPUContextPriority() override { return 0; };
+
 protected:
     IBinder* onAsBinder() override { return nullptr; }