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 99aed573b609e78462349eb86f24764eba38cb95..4f99bb4de1e9001dbb95d26cf8d954f2f6adb731 100755
--- a/src/gpu/GrDistanceFieldTextContext.cpp
+++ b/src/gpu/GrDistanceFieldTextContext.cpp
@@ -631,9 +631,11 @@ 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()) {
+
+            // TODO: move supportsRGBCoverage check to setupCoverageEffect and only add LCD
+            // processor if the xp can support it. For now we will simply assume that if
+            // fUseLCDText is true, then we have a known color output.
+            if (!drawState.getXPFactory()->supportsRGBCoverage(0, kRGBA_GrColorComponentFlags)) {
                 SkDebugf("LCD Text will not draw correctly.\n");
             }
             SkASSERT(!drawState.hasColorVertexAttribute());