Create swizzle table inside of glsl caps

src/gpu/gl/GrGLCaps.cpp

Index: src/gpu/gl/GrGLCaps.cpp
diff --git a/src/gpu/gl/GrGLCaps.cpp b/src/gpu/gl/GrGLCaps.cpp
index 1d25a2ca2f47eba5fcf1d4362387f9467983b1c4..c2e9627547b5383c311bfb5758ad0c4dd240da19 100644
--- a/src/gpu/gl/GrGLCaps.cpp
+++ b/src/gpu/gl/GrGLCaps.cpp
@@ -8,6 +8,7 @@
 
 #include "GrGLCaps.h"
 
+#include "GrContextOptions.h"
 #include "GrGLContext.h"
 #include "glsl/GrGLSLCaps.h"
 #include "SkTSearch.h"
@@ -27,7 +28,6 @@ GrGLCaps::GrGLCaps(const GrContextOptions& contextOptions,
     fMaxFragmentTextureUnits = 0;
     fRGBA8RenderbufferSupport = false;
     fBGRAIsInternalFormat = false;
-    fTextureSwizzleSupport = false;
     fUnpackRowLengthSupport = false;
     fUnpackFlipYSupport = false;
     fPackRowLengthSupport = false;
@@ -94,13 +94,6 @@ void GrGLCaps::init(const GrContextOptions& contextOptions,
     }
 
     if (kGL_GrGLStandard == standard) {
-        fTextureSwizzleSupport = version >= GR_GL_VER(3,3) ||
-                                 ctxInfo.hasExtension("GL_ARB_texture_swizzle");
-    } else {
-        fTextureSwizzleSupport = version >= GR_GL_VER(3,0);
-    }
-
-    if (kGL_GrGLStandard == standard) {
         fUnpackRowLengthSupport = true;
         fUnpackFlipYSupport = false;
         fPackRowLengthSupport = true;
@@ -491,6 +484,8 @@ void GrGLCaps::init(const GrContextOptions& contextOptions,
     this->initConfigTexturableTable(ctxInfo, gli, srgbSupport);
     this->initConfigRenderableTable(ctxInfo, srgbSupport);
     this->initShaderPrecisionTable(ctxInfo, gli, glslCaps);
+    // Requires fTexutreSwizzleSupport and fTextureRedSupport to be set before this point.
+    this->initConfigSwizzleTable(ctxInfo, glslCaps);
 
     this->applyOptionsOverrides(contextOptions);
     glslCaps->applyOptionsOverrides(contextOptions);
@@ -1169,7 +1164,6 @@ SkString GrGLCaps::dump() const {
     r.appendf("Max Vertex Attributes: %d\n", fMaxVertexAttributes);
     r.appendf("Support RGBA8 Render Buffer: %s\n", (fRGBA8RenderbufferSupport ? "YES": "NO"));
     r.appendf("BGRA is an internal format: %s\n", (fBGRAIsInternalFormat ? "YES": "NO"));
-    r.appendf("Support texture swizzle: %s\n", (fTextureSwizzleSupport ? "YES": "NO"));
     r.appendf("Unpack Row length support: %s\n", (fUnpackRowLengthSupport ? "YES": "NO"));
     r.appendf("Unpack Flip Y support: %s\n", (fUnpackFlipYSupport ? "YES": "NO"));
     r.appendf("Pack Row length support: %s\n", (fPackRowLengthSupport ? "YES": "NO"));
@@ -1280,6 +1274,44 @@ void GrGLCaps::initShaderPrecisionTable(const GrGLContextInfo& ctxInfo,
     }
 }
 
+void GrGLCaps::initConfigSwizzleTable(const GrGLContextInfo& ctxInfo, GrGLSLCaps* glslCaps) {
+    GrGLStandard standard = ctxInfo.standard();
+    GrGLVersion version = ctxInfo.version();
+
+    glslCaps->fMustSwizzleInShader = true;
+    if (kGL_GrGLStandard == standard) {
+        if (version >= GR_GL_VER(3,3) || ctxInfo.hasExtension("GL_ARB_texture_swizzle")) {
+            glslCaps->fMustSwizzleInShader = false;
+        }
+    } else {
+        if (version >= GR_GL_VER(3,0)) {
+            glslCaps->fMustSwizzleInShader = false;
+        }
+    }
+
+    glslCaps->fConfigSwizzle[kUnknown_GrPixelConfig] = nullptr;
+    if (fTextureRedSupport) {
+        glslCaps->fConfigSwizzle[kAlpha_8_GrPixelConfig] = "rrrr";
+        glslCaps->fConfigSwizzle[kAlpha_half_GrPixelConfig] = "rrrr";
+    } else {
+        glslCaps->fConfigSwizzle[kAlpha_8_GrPixelConfig] = "aaaa";
+        glslCaps->fConfigSwizzle[kAlpha_half_GrPixelConfig] = "aaaa";
+    }
+    glslCaps->fConfigSwizzle[kIndex_8_GrPixelConfig] = "rgba";
+    glslCaps->fConfigSwizzle[kRGB_565_GrPixelConfig] = "rgba";
+    glslCaps->fConfigSwizzle[kRGBA_4444_GrPixelConfig] = "rgba";
+    glslCaps->fConfigSwizzle[kRGBA_8888_GrPixelConfig] = "rgba";
+    glslCaps->fConfigSwizzle[kBGRA_8888_GrPixelConfig] = "rgba";
+    glslCaps->fConfigSwizzle[kSRGBA_8888_GrPixelConfig] = "rgba";
+    glslCaps->fConfigSwizzle[kETC1_GrPixelConfig] = "rgba";
+    glslCaps->fConfigSwizzle[kLATC_GrPixelConfig] = "rrrr";
+    glslCaps->fConfigSwizzle[kR11_EAC_GrPixelConfig] = "rrrr";
+    glslCaps->fConfigSwizzle[kASTC_12x12_GrPixelConfig] = "rgba";
+    glslCaps->fConfigSwizzle[kRGBA_float_GrPixelConfig] = "rgba";
+    glslCaps->fConfigSwizzle[kRGBA_half_GrPixelConfig] = "rgba";
+
+}
 
+void GrGLCaps::onApplyOptionsOverrides(const GrContextOptions& options) {}