Revert of sRGB support in Ganesh. Several pieces:

include/gpu/GrColor.h

Index: include/gpu/GrColor.h
diff --git a/include/gpu/GrColor.h b/include/gpu/GrColor.h
index 77f1a6cb0841aa84d1f073ea7265d28438cc2b02..6b83237626ae590746757ac28ce22b9a5c22a3f8 100644
--- a/include/gpu/GrColor.h
+++ b/include/gpu/GrColor.h
@@ -208,6 +208,7 @@
 }
 
 static inline uint32_t GrPixelConfigComponentMask(GrPixelConfig config) {
+    SkASSERT(config >= 0 && config < kGrPixelConfigCnt);
     static const uint32_t kFlags[] = {
         0,                              // kUnknown_GrPixelConfig
         kA_GrColorComponentFlag,        // kAlpha_8_GrPixelConfig
@@ -217,7 +218,6 @@
         kRGBA_GrColorComponentFlags,    // kRGBA_8888_GrPixelConfig
         kRGBA_GrColorComponentFlags,    // kBGRA_8888_GrPixelConfig
         kRGBA_GrColorComponentFlags,    // kSRGBA_8888_GrPixelConfig
-        kRGBA_GrColorComponentFlags,    // kSBGRA_8888_GrPixelConfig
         kRGB_GrColorComponentFlags,     // kETC1_GrPixelConfig
         kA_GrColorComponentFlag,        // kLATC_GrPixelConfig
         kA_GrColorComponentFlag,        // kR11_EAC_GrPixelConfig
@@ -236,14 +236,13 @@
     GR_STATIC_ASSERT(5  == kRGBA_8888_GrPixelConfig);
     GR_STATIC_ASSERT(6  == kBGRA_8888_GrPixelConfig);
     GR_STATIC_ASSERT(7  == kSRGBA_8888_GrPixelConfig);
-    GR_STATIC_ASSERT(8  == kSBGRA_8888_GrPixelConfig);
-    GR_STATIC_ASSERT(9  == kETC1_GrPixelConfig);
-    GR_STATIC_ASSERT(10  == kLATC_GrPixelConfig);
-    GR_STATIC_ASSERT(11  == kR11_EAC_GrPixelConfig);
-    GR_STATIC_ASSERT(12 == kASTC_12x12_GrPixelConfig);
-    GR_STATIC_ASSERT(13 == kRGBA_float_GrPixelConfig);
-    GR_STATIC_ASSERT(14 == kAlpha_half_GrPixelConfig);
-    GR_STATIC_ASSERT(15 == kRGBA_half_GrPixelConfig);
+    GR_STATIC_ASSERT(8  == kETC1_GrPixelConfig);
+    GR_STATIC_ASSERT(9  == kLATC_GrPixelConfig);
+    GR_STATIC_ASSERT(10  == kR11_EAC_GrPixelConfig);
+    GR_STATIC_ASSERT(11 == kASTC_12x12_GrPixelConfig);
+    GR_STATIC_ASSERT(12 == kRGBA_float_GrPixelConfig);
+    GR_STATIC_ASSERT(13 == kAlpha_half_GrPixelConfig);
+    GR_STATIC_ASSERT(14 == kRGBA_half_GrPixelConfig);
     GR_STATIC_ASSERT(SK_ARRAY_COUNT(kFlags) == kGrPixelConfigCnt);
 }