Don't leak fragment processor in SkColorFilter::asFragmentProcessors implementations.

src/effects/SkColorFilters.cpp

Index: src/effects/SkColorFilters.cpp
diff --git a/src/effects/SkColorFilters.cpp b/src/effects/SkColorFilters.cpp
index 30b550bcc00887ae63f8cd63935d8b5bbcf03aef..1bb9f8fb153b138d64975cffc3b0b6257f41c549 100644
--- a/src/effects/SkColorFilters.cpp
+++ b/src/effects/SkColorFilters.cpp
@@ -369,6 +369,9 @@ bool SkModeColorFilter::asFragmentProcessors(GrContext*,
         if (frag) {
             if (array) {
                 *array->append() = frag;
+            } else {
+                frag->unref();
+                SkDEBUGCODE(frag = NULL;)
             }
             return true;
         }