Auto-compare GrProcessors' texture accesses in isEqual().

src/effects/SkAlphaThresholdFilter.cpp

Index: src/effects/SkAlphaThresholdFilter.cpp
diff --git a/src/effects/SkAlphaThresholdFilter.cpp b/src/effects/SkAlphaThresholdFilter.cpp
index 016780fb0118825e5e9033e3819d727f11842f1a..7e91af4f4b4c1a50be1c0b37eb9825e12ecfeb88 100644
--- a/src/effects/SkAlphaThresholdFilter.cpp
+++ b/src/effects/SkAlphaThresholdFilter.cpp
@@ -223,8 +223,7 @@ const GrBackendFragmentProcessorFactory& AlphaThresholdEffect::getFactory() cons
 
 bool AlphaThresholdEffect::onIsEqual(const GrFragmentProcessor& sBase) const {
     const AlphaThresholdEffect& s = sBase.cast<AlphaThresholdEffect>();
-    return (this->texture(0) == s.texture(0) &&
-            this->fInnerThreshold == s.fInnerThreshold &&
+    return (this->fInnerThreshold == s.fInnerThreshold &&
             this->fOuterThreshold == s.fOuterThreshold);
 }