SkImage now has makeShader to return sk_sp

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1785473002

Review URL: https://codereview.chromium.org/1785473002
diff --git a/src/gpu/SkGpuDevice.cpp b/src/gpu/SkGpuDevice.cpp
index a7bf82e..7a6d967 100644
--- a/src/gpu/SkGpuDevice.cpp
+++ b/src/gpu/SkGpuDevice.cpp
@@ -1678,7 +1678,7 @@
     GR_CREATE_TRACE_MARKER_CONTEXT("SkGpuDevice", "drawText", fContext);
 
     SkPaint p(paint);
-    p.setShader(atlas->newShader(SkShader::kClamp_TileMode, SkShader::kClamp_TileMode))->unref();
+    p.setShader(atlas->makeShader(SkShader::kClamp_TileMode, SkShader::kClamp_TileMode));
 
     GrPaint grPaint;
     if (colors) {