SkCodec: add wbmp class

Review URL: https://codereview.chromium.org/1006583005
diff --git a/gyp/tests.gypi b/gyp/tests.gypi
index 049b4b2..e69f2b0 100644
--- a/gyp/tests.gypi
+++ b/gyp/tests.gypi
@@ -75,6 +75,7 @@
     '../tests/ClipCubicTest.cpp',
     '../tests/ClipStackTest.cpp',
     '../tests/ClipperTest.cpp',
+    '../tests/CodexTest.cpp',
     '../tests/ColorFilterTest.cpp',
     '../tests/ColorPrivTest.cpp',
     '../tests/ColorTest.cpp',