Support buildLayer in new pipeline

bug:26561995
bug:27620686

Change-Id: I6c39f9a077e7e6002d3c01b8888238fd17b0f02a
diff --git a/libs/hwui/renderthread/CanvasContext.h b/libs/hwui/renderthread/CanvasContext.h
index 6706c30..6d0889e 100644
--- a/libs/hwui/renderthread/CanvasContext.h
+++ b/libs/hwui/renderthread/CanvasContext.h
@@ -196,10 +196,11 @@
     RingBuffer<SwapHistory, 3> mSwapHistory;
 
     bool mOpaque;
-    OpenGLRenderer* mCanvas = nullptr;
 #if HWUI_NEW_OPS
     BakedOpRenderer::LightInfo mLightInfo;
     FrameBuilder::LightGeometry mLightGeometry = { {0, 0, 0}, 0 };
+#else
+    OpenGLRenderer* mCanvas = nullptr;
 #endif
 
     bool mHaveNewSurface = false;