Cache render targets that render to wrapped textures

src/core/SkImageFilter.cpp

Index: src/core/SkImageFilter.cpp
diff --git a/src/core/SkImageFilter.cpp b/src/core/SkImageFilter.cpp
index 524a475b71311c65306b6fa65c2125da100894df..56a22a8ac3ae0bac3625de139324feeee47f6699 100644
--- a/src/core/SkImageFilter.cpp
+++ b/src/core/SkImageFilter.cpp
@@ -26,6 +26,7 @@
 #if SK_SUPPORT_GPU
 #include "GrContext.h"
 #include "GrDrawContext.h"
+#include "GrGpuResourcePriv.h"
 #include "SkGrPixelRef.h"
 #include "SkGr.h"
 #endif
@@ -735,6 +736,10 @@ public:
     }
 
     void set(const Key& key, SkSpecialImage* image, const SkIPoint& offset) override {
+#if SK_SUPPORT_GPU
+        SkASSERT(!image->peekTexture() ||
+                 !image->peekTexture()->resourcePriv().refsWrappedResources());
+#endif
         SkAutoMutexAcquire mutex(fMutex);
         if (Value* v = fLookup.find(key)) {
             this->removeInternal(v);