Clean up unused or overly complex modes in SkSwizzler

src/codec/SkSwizzler.h

Index: src/codec/SkSwizzler.h
diff --git a/src/codec/SkSwizzler.h b/src/codec/SkSwizzler.h
index e75ab43cfe0c90c5daf0f313443d0624bec0b859..cca4844deae84b23aa1e313b66789d421167d420 100644
--- a/src/codec/SkSwizzler.h
+++ b/src/codec/SkSwizzler.h
@@ -28,12 +28,15 @@ public:
         kIndex,
         kRGB,
         kBGR,
-        kRGBX,
         kBGRX,

[msarett, 2016/01/14 20:52:24]

kBGRX now really means BGR(anything) instead of BGR(FF).

[scroggo, 2016/01/14 21:28:18]

Can you add a comment stating that?

[msarett, 2016/01/14 22:25:20]

Done.

         kRGBA,
         kBGRA,
-        kRGB_565,
         kCMYK,
+        // These modes are used exclusively for sampling and subsetting.

[scroggo, 2016/01/14 21:28:18]

Looks like the number means the number of bytes. That may be obvious enough (we
already assume the other ones above mean number of bits).

[msarett, 2016/01/14 22:25:20]

Happy to use the number of bits for consistency.

+        // The pixels themselves do not need to be modified.
+        kNOOP1,

[scroggo, 2016/01/14 21:28:18]

Why not kNoOp1 etc?

[msarett, 2016/01/14 22:25:20]

sgtm

+        kNOOP2,
+        kNOOP4,
     };
 
     /*
@@ -52,17 +55,18 @@ public:
                 return 4;
             case kGray:
             case kIndex:
+            case kNOOP1:
                 return 8;
-            case kRGB_565:
+            case kNOOP2:
                 return 16;
             case kRGB:
             case kBGR:
                 return 24;
-            case kRGBX:
             case kRGBA:
             case kBGRX:
             case kBGRA:
             case kCMYK:
+            case kNOOP4:
                 return 32;
             default:
                 SkASSERT(false);