Remove unneeded GrGLSLTransformedCoordsArray type

Rename GrGLSLFragmentBuilder::ensureFSCoords2D to ensureCoords2D and make it take an arbitrary GrShaderVar.
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Review-Url: https://codereview.chromium.org/2324663004
diff --git a/src/gpu/effects/GrSimpleTextureEffect.cpp b/src/gpu/effects/GrSimpleTextureEffect.cpp
index b819cf3..6eb15e0 100644
--- a/src/gpu/effects/GrSimpleTextureEffect.cpp
+++ b/src/gpu/effects/GrSimpleTextureEffect.cpp
@@ -24,8 +24,8 @@
         fragBuilder->codeAppendf("%s = ", args.fOutputColor);
         fragBuilder->appendTextureLookupAndModulate(args.fInputColor,
                                                     args.fTexSamplers[0],
-                                                    args.fCoords[0].c_str(),
-                                                    args.fCoords[0].getType(),
+                                                    args.fTransformedCoords[0].c_str(),
+                                                    args.fTransformedCoords[0].getType(),
                                                     &colorSpaceHelper);
         fragBuilder->codeAppend(";");
     }