Roll external/skia 4dc5a4540..969be1c98 (6 commits)

https://skia.googlesource.com/skia.git/+log/4dc5a4540..969be1c98

2018-05-21 bsalomon@google.com Remove mask-filters and aa from SkPaint in SkCanvas for nine-patch/lattice.
2018-05-21 benjaminwagner@google.com Omit failing test.
2018-05-21 enne@chromium.org Fix unit tests when workarounds are enabled
2018-05-21 egdaniel@google.com Reland "Remove GrBackendObject and all related functions from Skia."
2018-05-21 bsalomon@google.com Add perspective support to GrTextureOp.
2018-05-21 egdaniel@google.com Move gn setup for vulkan library/headers into their own third_party directory.

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Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

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Change-Id: Idccc3baf089598b0d677aaea42894a08f8087079
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diff --git a/Android.bp b/Android.bp
index 68a3fac..c00be4d 100644
--- a/Android.bp
+++ b/Android.bp
@@ -1340,6 +1340,7 @@
         "gm/pathreverse.cpp",
         "gm/pdf_never_embed.cpp",
         "gm/perlinnoise.cpp",
+        "gm/perspimages.cpp",
         "gm/perspshaders.cpp",
         "gm/picture.cpp",
         "gm/pictureimagefilter.cpp",
@@ -2290,6 +2291,7 @@
         "gm/pathreverse.cpp",
         "gm/pdf_never_embed.cpp",
         "gm/perlinnoise.cpp",
+        "gm/perspimages.cpp",
         "gm/perspshaders.cpp",
         "gm/picture.cpp",
         "gm/pictureimagefilter.cpp",