Modifications to get 'blaze build -c opt //third_party/skia/HEAD/...' to work.

BUG=skia:

Review URL: https://codereview.chromium.org/1413973002
diff --git a/BUILD.public b/BUILD.public
index 832b3ad..d806214 100644
--- a/BUILD.public
+++ b/BUILD.public
@@ -219,6 +219,7 @@
 
 COPTS = [
     "-Wno-implicit-fallthrough",  # Some intentional fallthrough.
+    "-Wno-deprecated-declarations",  # Internal use of deprecated methods. :(
 ]
 
 DEFINES = [