Add sRGB texture support.

include/gpu/GrTypes.h

Index: include/gpu/GrTypes.h
diff --git a/include/gpu/GrTypes.h b/include/gpu/GrTypes.h
index 4e225f0cb997f43738aa5a38e6100f6201ce75d5..6ce4f527f25810a3521979944b23c696d5870e00 100644
--- a/include/gpu/GrTypes.h
+++ b/include/gpu/GrTypes.h
@@ -271,6 +271,10 @@ enum GrPixelConfig {
      */
     kBGRA_8888_GrPixelConfig,
     /**
+     * Premultiplied and sRGB. Byte order is r,g,b,a.
+     */
+    kSRGBA_8888_GrPixelConfig,
+    /**
      * ETC1 Compressed Data
      */
     kETC1_GrPixelConfig,
@@ -342,6 +346,7 @@ static inline bool GrPixelConfigIs8888(GrPixelConfig config) {
     switch (config) {
         case kRGBA_8888_GrPixelConfig:
         case kBGRA_8888_GrPixelConfig:
+        case kSRGBA_8888_GrPixelConfig:
             return true;
         default:
             return false;
@@ -372,6 +377,7 @@ static inline size_t GrBytesPerPixel(GrPixelConfig config) {
             return 2;
         case kRGBA_8888_GrPixelConfig:
         case kBGRA_8888_GrPixelConfig:
+        case kSRGBA_8888_GrPixelConfig:
             return 4;
         case kRGBA_float_GrPixelConfig:
             return 16;
@@ -391,6 +397,7 @@ static inline size_t GrUnpackAlignment(GrPixelConfig config) {
             return 2;
         case kRGBA_8888_GrPixelConfig:
         case kBGRA_8888_GrPixelConfig:
+        case kSRGBA_8888_GrPixelConfig:
         case kRGBA_float_GrPixelConfig:
             return 4;
         default: