Revert of modify nothingToDraw to notice filters

tests/PaintTest.cpp

Index: tests/PaintTest.cpp
diff --git a/tests/PaintTest.cpp b/tests/PaintTest.cpp
index c307aa94bcd9d67a58e316c165aca4c50e3175f2..4c45eed7614c368e270c47f3f1249f22b1223575 100644
--- a/tests/PaintTest.cpp
+++ b/tests/PaintTest.cpp
@@ -344,30 +344,3 @@
     paint.setHinting(SkPaint::kNormal_Hinting);
     REPORTER_ASSERT(r, paint.getHash() == defaultHash);
 }
-
-#include "SkColorMatrixFilter.h"
-
-DEF_TEST(Paint_nothingToDraw, r) {
-    SkPaint paint;
-
-    REPORTER_ASSERT(r, !paint.nothingToDraw());
-    paint.setAlpha(0);
-    REPORTER_ASSERT(r, paint.nothingToDraw());
-
-    paint.setAlpha(0xFF);
-    paint.setXfermodeMode(SkXfermode::kDst_Mode);
-    REPORTER_ASSERT(r, paint.nothingToDraw());
-
-    paint.setAlpha(0);
-    paint.setXfermodeMode(SkXfermode::kSrcOver_Mode);
-
-    SkColorMatrix cm;
-    cm.setIdentity();   // does not change alpha
-    paint.setColorFilter(SkColorMatrixFilter::Create(cm))->unref();
-    REPORTER_ASSERT(r, paint.nothingToDraw());
-
-    cm.postTranslate(0, 0, 0, 1);    // wacks alpha
-    paint.setColorFilter(SkColorMatrixFilter::Create(cm))->unref();
-    REPORTER_ASSERT(r, !paint.nothingToDraw());
-}
-