Fix matrix mapping of negative rects

bug:27381362

Also rejects ops with empty clip at record time, and short circuits clip
intersection, when one is empty.

Change-Id: I842612da14ad8fd9f1ba5e9e4fd027ba4e08d365
diff --git a/libs/hwui/Android.mk b/libs/hwui/Android.mk
index da7b7fb..70995ac 100644
--- a/libs/hwui/Android.mk
+++ b/libs/hwui/Android.mk
@@ -242,6 +242,7 @@
     tests/unit/GpuMemoryTrackerTests.cpp \
     tests/unit/LayerUpdateQueueTests.cpp \
     tests/unit/LinearAllocatorTests.cpp \
+    tests/unit/MatrixTests.cpp \
     tests/unit/OffscreenBufferPoolTests.cpp \
     tests/unit/SkiaBehaviorTests.cpp \
     tests/unit/StringUtilsTests.cpp \