fix memory leak, remake Imageshader to use sk_sp

src/image/SkImage.cpp

Index: src/image/SkImage.cpp
diff --git a/src/image/SkImage.cpp b/src/image/SkImage.cpp
index 921bc6f5d7bf99860709f18a355b2e449f7d2308..9febeaa96e12daf5d4d962a755688dd35562e97b 100644
--- a/src/image/SkImage.cpp
+++ b/src/image/SkImage.cpp
@@ -108,7 +108,7 @@ void SkImage::preroll(GrContext* ctx) const {
 
 sk_sp<SkShader> SkImage::makeShader(SkShader::TileMode tileX, SkShader::TileMode tileY,
                                     const SkMatrix* localMatrix) const {
-    return SkImageShader::Make(this, tileX, tileY, localMatrix);
+    return SkImageShader::Make(sk_ref_sp(const_cast<SkImage*>(this)), tileX, tileY, localMatrix);
 }
 
 #ifdef SK_SUPPORT_LEGACY_CREATESHADER_PTR