Add null check for bmp->tex result in SkImageFilter::filterInputGpu

src/core/SkImageFilter.cpp

Index: src/core/SkImageFilter.cpp
diff --git a/src/core/SkImageFilter.cpp b/src/core/SkImageFilter.cpp
index eec6d3a7e87da85e08fa0a15b4abe030222368cf..95988f844c4c7ef7c96394295b8de185478c1e28 100644
--- a/src/core/SkImageFilter.cpp
+++ b/src/core/SkImageFilter.cpp
@@ -544,7 +544,10 @@ bool SkImageFilter::filterInputGPU(int index, SkImageFilter::Proxy* proxy,
                 return false;
             }
             SkAutoTUnref<GrTexture> resultTex(
-                GrRefCachedBitmapTexture(context, *result,GrTextureParams::ClampNoFilter()));
+                GrRefCachedBitmapTexture(context, *result, GrTextureParams::ClampNoFilter()));
+            if (!resultTex) {
+                return false;
+            }
             result->setPixelRef(new SkGrPixelRef(info, resultTex))->unref();
         }
         return true;