Handle nullptr from asTextureRef

src/image/SkImage.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkBitmapCache.h"
 #include "SkCanvas.h"
@@ skipping 333 matching lines @@
 
     if (!result) {
         return nullptr;
     }
 
     SkIRect fullSize = SkIRect::MakeWH(result->width(), result->height());
 #if SK_SUPPORT_GPU
     if (result->isTextureBacked()) {
         GrContext* context = result->getContext();
         sk_sp<GrTexture> texture = result->asTextureRef(context);
+        if (!texture) {
+            return nullptr;
+        }
         fullSize = SkIRect::MakeWH(texture->width(), texture->height());
     }
 #endif
     *outSubset = SkIRect::MakeWH(result->width(), result->height());
     if (!outSubset->intersect(clipBounds.makeOffset(-offset->x(), -offset->y()))) {
         return nullptr;
     }
     offset->fX += outSubset->x();
     offset->fY += outSubset->y();
     // This isn't really a "tight" subset, but includes any texture padding.
@@ skipping 85 matching lines @@
     SkASSERT(image);
     SkASSERT(ctx);
     return as_IB(image)->onPinAsTexture(ctx);
 }
 
 void SkImage_unpinAsTexture(const SkImage* image, GrContext* ctx) {
     SkASSERT(image);
     SkASSERT(ctx);
     as_IB(image)->onUnpinAsTexture(ctx);
 }