Add XferProcessor factory in GrPaint and GrDrawState.

src/gpu/GrDistanceFieldTextContext.cpp

Index: src/gpu/GrDistanceFieldTextContext.cpp
diff --git a/src/gpu/GrDistanceFieldTextContext.cpp b/src/gpu/GrDistanceFieldTextContext.cpp
index a012bc28b7f9e2929b8349ee4ed5e43d6ae74e05..bb493cbf0a1c9732f3baebf87149f6c42fca2794 100755
--- a/src/gpu/GrDistanceFieldTextContext.cpp
+++ b/src/gpu/GrDistanceFieldTextContext.cpp
@@ -660,9 +660,7 @@ void GrDistanceFieldTextContext::flush() {
         // Set draw state
         if (fUseLCDText) {
             GrColor colorNoPreMul = skcolor_to_grcolor_nopremultiply(filteredColor);
-            if (kOne_GrBlendCoeff != fPaint.getSrcBlendCoeff() ||
-                kISA_GrBlendCoeff != fPaint.getDstBlendCoeff() ||
-                fPaint.numColorStages()) {
+            if (!drawState.getXPFactory()->supportsRGBCoverage(drawState)) {
                 SkDebugf("LCD Text will not draw correctly.\n");
             }
             SkASSERT(!drawState.hasColorVertexAttribute());