sRGB support in Ganesh. Several pieces:

include/gpu/GrTypes.h

Index: include/gpu/GrTypes.h
diff --git a/include/gpu/GrTypes.h b/include/gpu/GrTypes.h
index 3def9aaa993df434948afe15cf8263d655f42776..409d26080209f7e575fce61100307e943144fb77 100644
--- a/include/gpu/GrTypes.h
+++ b/include/gpu/GrTypes.h
@@ -218,6 +218,10 @@ enum GrPixelConfig {
      */
     kSRGBA_8888_GrPixelConfig,
     /**
+     * Premultiplied and sRGB. Byte order is b,g,r,a.
+     */
+    kSBGRA_8888_GrPixelConfig,
+    /**
      * ETC1 Compressed Data
      */
     kETC1_GrPixelConfig,
@@ -268,8 +272,10 @@ static const int kGrPixelConfigCnt = kLast_GrPixelConfig + 1;
 #endif
 #if SK_PMCOLOR_BYTE_ORDER(B,G,R,A)
     static const GrPixelConfig kSkia8888_GrPixelConfig = kBGRA_8888_GrPixelConfig;
+    static const GrPixelConfig kSkiaGamma8888_GrPixelConfig = kSBGRA_8888_GrPixelConfig;
 #elif SK_PMCOLOR_BYTE_ORDER(R,G,B,A)
     static const GrPixelConfig kSkia8888_GrPixelConfig = kRGBA_8888_GrPixelConfig;
+    static const GrPixelConfig kSkiaGamma8888_GrPixelConfig = kSRGBA_8888_GrPixelConfig;
 #else
     #error "SK_*32_SHIFT values must correspond to GL_BGRA or GL_RGBA format."
 #endif
@@ -311,6 +317,7 @@ static inline bool GrPixelConfigIs8888(GrPixelConfig config) {
         case kRGBA_8888_GrPixelConfig:
         case kBGRA_8888_GrPixelConfig:
         case kSRGBA_8888_GrPixelConfig:
+        case kSBGRA_8888_GrPixelConfig:
             return true;
         default:
             return false;
@@ -322,6 +329,7 @@ static inline bool GrPixelConfigIs8888(GrPixelConfig config) {
 static inline bool GrPixelConfigIsSRGB(GrPixelConfig config) {
     switch (config) {
         case kSRGBA_8888_GrPixelConfig:
+        case kSBGRA_8888_GrPixelConfig:
             return true;
         default:
             return false;
@@ -336,6 +344,10 @@ static inline GrPixelConfig GrPixelConfigSwapRAndB(GrPixelConfig config) {
             return kRGBA_8888_GrPixelConfig;
         case kRGBA_8888_GrPixelConfig:
             return kBGRA_8888_GrPixelConfig;
+        case kSBGRA_8888_GrPixelConfig:
+            return kSRGBA_8888_GrPixelConfig;
+        case kSRGBA_8888_GrPixelConfig:
+            return kSBGRA_8888_GrPixelConfig;
         default:
             return kUnknown_GrPixelConfig;
     }
@@ -353,6 +365,7 @@ static inline size_t GrBytesPerPixel(GrPixelConfig config) {
         case kRGBA_8888_GrPixelConfig:
         case kBGRA_8888_GrPixelConfig:
         case kSRGBA_8888_GrPixelConfig:
+        case kSBGRA_8888_GrPixelConfig:
             return 4;
         case kRGBA_half_GrPixelConfig:
             return 8;
@@ -387,6 +400,25 @@ static inline bool GrPixelConfigIsAlphaOnly(GrPixelConfig config) {
 }
 
 /**
+ * What to do with sRGB source data for a particular device?
+ */
+enum GrSRGBPolicy {
+    kUnknown_GrSRGBPolicy,

[bsalomon, 2016/03/17 14:54:47]

What does unknown mean? Can we get away with just allow and suppress and at bind
time suppress if either params or the value implied by the config says suppress?

[Brian Osman, 2016/03/17 15:01:21]

Currently, the only use of the params override is to force "Allow" (not
"Suppress"). We could shrink the enum and put an extra boolean on texture params
that indicates if the value should be used. That limits the scope of the 'third
state', but didn't feel much better than this solution. (I agree that this is
klunky - I tried to come up with a better solution when I added this,
particularly because it makes the code in bindTexture somewhat trickier to
read).

+    kAllowSRGB_GrSRGBPolicy,
+    kSuppressSRGB_GrSRGBPolicy,
+};
+
+static inline GrSRGBPolicy GrPixelConfigSRGBPolicy(GrPixelConfig config) {
+    switch (config) {
+        case kRGBA_8888_GrPixelConfig:
+        case kBGRA_8888_GrPixelConfig:
+            return kSuppressSRGB_GrSRGBPolicy;
+        default:
+            return kAllowSRGB_GrSRGBPolicy;
+    }
+}
+
+/**
  * Optional bitfield flags that can be set on GrSurfaceDesc (below).
  */
 enum GrSurfaceFlags {