test-hwc2: set layer z order

Test: Add "#define HAVE_NO_SURFACE_FLINGER" to
          frameworks/native/libs/gui/BufferQueueCore.cpp.
      Recompile and flash.
      Run "mm" in frameworks/native/services/surfaceflinger/tests/hwc2.
      Push test-hwc2 to device.
      Run "adb root && adb shell stop".
      Run test case. Ex: "./test-hwc2"

Change-Id: I2c51df36d62f9d809583003b81c24dbd7a744301
diff --git a/services/surfaceflinger/tests/hwc2/Hwc2TestLayer.h b/services/surfaceflinger/tests/hwc2/Hwc2TestLayer.h
index d259ad9..855f7bb 100644
--- a/services/surfaceflinger/tests/hwc2/Hwc2TestLayer.h
+++ b/services/surfaceflinger/tests/hwc2/Hwc2TestLayer.h
@@ -27,7 +27,7 @@
 
 class Hwc2TestLayer {
 public:
-    Hwc2TestLayer(Hwc2TestCoverage coverage);
+    Hwc2TestLayer(Hwc2TestCoverage coverage, uint32_t zOrder = 0);
 
     std::string dump() const;
 
@@ -38,6 +38,7 @@
     android_dataspace_t    getDataspace() const;
     float                  getPlaneAlpha() const;
     hwc_transform_t        getTransform() const;
+    uint32_t               getZOrder() const;
 
     bool advanceBlendMode();
     bool advanceComposition();
@@ -55,6 +56,8 @@
     Hwc2TestDataspace mDataspace;
     Hwc2TestPlaneAlpha mPlaneAlpha;
     Hwc2TestTransform mTransform;
+
+    uint32_t mZOrder;
 };
 
 #endif /* ifndef _HWC2_TEST_LAYER_H */