Revert of sRGB support in Ganesh. Several pieces: (patchset #12 id:220001 of https://codereview.chromium.org/1789663002/ )

Reason for revert:
We're getting sRGB non-8888 configs?

Original issue's description:
> sRGB support in Ganesh. Several pieces:
>
> sRGB support now also requires GL_EXT_texture_sRGB_decode, which allows
> us to disable sRGB -> Linear conversion when reading textures. This gives
> us an easy way to support "legacy" L32 mode. We disable decoding based on
> the pixel config of the render target. Textures can override that behavior
> (specifically for format-conversion draws where we want that behavior).
>
> Added sBGRA pixel config, which is not-really-a-format. It's just sRGBA
> internally, and the external format is BGR order, so TexImage calls will
> swizzle correctly. This lets us interact with sRGB raster surfaces on BGR
> platforms.
>
> Devices without sRGB support behave like they always have: conversion from
> color type and profile type ignores sRGB and always returns linear pixel
> configs.
>
> BUG=skia:
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1789663002
>
> Committed: https://skia.googlesource.com/skia/+/9e3f1bf4e5cd8fc59554f986f36d6b034e99f9eb

TBR=reed@google.com,bsalomon@google.com,robertphillips@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/1814533003
diff --git a/src/gpu/GrCaps.cpp b/src/gpu/GrCaps.cpp
index 000f90c6..c544d6e 100644
--- a/src/gpu/GrCaps.cpp
+++ b/src/gpu/GrCaps.cpp
@@ -83,7 +83,6 @@
 GrCaps::GrCaps(const GrContextOptions& options) {
     fMipMapSupport = false;
     fNPOTTextureTileSupport = false;
-    fSRGBSupport = false;
     fTwoSidedStencilSupport = false;
     fStencilWrapOpsSupport = false;
     fDiscardRenderTargetSupport = false;
@@ -158,7 +157,6 @@
     static const char* gNY[] = {"NO", "YES"};
     r.appendf("MIP Map Support                    : %s\n", gNY[fMipMapSupport]);
     r.appendf("NPOT Texture Tile Support          : %s\n", gNY[fNPOTTextureTileSupport]);
-    r.appendf("sRGB Support                       : %s\n", gNY[fSRGBSupport]);
     r.appendf("Two Sided Stencil Support          : %s\n", gNY[fTwoSidedStencilSupport]);
     r.appendf("Stencil Wrap Ops  Support          : %s\n", gNY[fStencilWrapOpsSupport]);
     r.appendf("Discard Render Target Support      : %s\n", gNY[fDiscardRenderTargetSupport]);
@@ -212,7 +210,6 @@
         "RGBA8888", // kRGBA_8888_GrPixelConfig,
         "BGRA8888", // kBGRA_8888_GrPixelConfig,
         "SRGBA8888",// kSRGBA_8888_GrPixelConfig,
-        "SBGRA8888",// kSBGRA_8888_GrPixelConfig,
         "ETC1",     // kETC1_GrPixelConfig,
         "LATC",     // kLATC_GrPixelConfig,
         "R11EAC",   // kR11_EAC_GrPixelConfig,
@@ -229,14 +226,13 @@
     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(kConfigNames) == kGrPixelConfigCnt);
 
     SkASSERT(!this->isConfigRenderable(kUnknown_GrPixelConfig, false));