Individually enable and disable SkCodecs

public.bzl

Index: public.bzl
diff --git a/public.bzl b/public.bzl
index 32cb2de7864dfa04ba30db38dff496976b794648..39516bbaf5a2335c55a96a6ff05126ab214cf5ea 100644
--- a/public.bzl
+++ b/public.bzl
@@ -484,8 +484,6 @@ DEFINES_UNIX = [
 
 DEFINES_ANDROID = [
     "SK_BUILD_FOR_ANDROID",
-    # TODO(benjaminwagner): Try to get png library updated?

[msarett, 2016/02/16 22:24:22]

INDEX_SUPPORTED is not a feature of a newer libpng.  It is a feature of
Android's forked libpng (which we have recently removed :)).  We intentionally
don't support this anymore.

-    "SK_PNG_NO_INDEX_SUPPORTED",
     "SK_CODEC_DECODES_RAW",
 ]
 
@@ -501,6 +499,14 @@ DEFINES_ALL = [
     "SK_USE_FREETYPE_EMBOLDEN",
     # Turn on a few Google3-specific build fixes.
     "GOOGLE3",
+    # Turn on image codecs

[dogben, 2016/02/16 22:31:16]

We have removed all dependencies for the iOS Google3 build. Could you add these
to DEFINES_UNIX and DEFINES_ANDROID instead?

[msarett, 2016/02/16 22:33:54]

Yes.  Though we should be able to keep BMP and WBMP here, since they have no
dependencies.

How does this work now?  Ex: It seems like JPEG is always enabled, yet there are
no libjpegs on iOS?

[msarett, 2016/02/17 14:34:53]

Thanks, removing these on iOS.

+    "SK_CODEC_DECODES_BMP",
+    "SK_CODEC_DECODES_GIF",
+    "SK_CODEC_DECODES_ICO",
+    "SK_CODEC_DECODES_JPEG",
+    "SK_CODEC_DECODES_PNG",
+    "SK_CODEC_DECODES_WBMP",
+    "SK_CODEC_DECODES_WEBP",
 ]
 
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