Create EGLImages during buffer allocation

EGLImage creation is now performed on an async binder thread, so now GPU
composition should rarely be stalled by expensive image creation.

Bug: 129008989
Test: systrace
Change-Id: I9732f866933a8950a4c69ff51d5ac1622bbb3470
diff --git a/libs/gui/ConsumerBase.cpp b/libs/gui/ConsumerBase.cpp
index abd9921..1e94cc1 100644
--- a/libs/gui/ConsumerBase.cpp
+++ b/libs/gui/ConsumerBase.cpp
@@ -131,6 +131,8 @@
     }
 }
 
+void ConsumerBase::onBufferAllocated(const BufferItem& /*item*/) {}
+
 void ConsumerBase::onBuffersReleased() {
     Mutex::Autolock lock(mMutex);