Fix bug of SkSVGCanvas::Make

The method `SkSVGCanvas::Make(const SkRect& bounds, SkWStream* writer)`
passes a pointer to a stack-allocated object to the returned SkCanvas.

TBR=
Change-Id: Ica7933adc59764a69eb2fb6312df91ffffd5627b
Reviewed-on: https://skia-review.googlesource.com/c/192040
Commit-Queue: Florin Malita <fmalita@chromium.org>
Reviewed-by: Mike Reed <reed@google.com>
Reviewed-by: Florin Malita <fmalita@chromium.org>
diff --git a/AUTHORS b/AUTHORS
index a0fd225..ff6fc6c 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -54,3 +54,4 @@
 Kaloyan Donev <kdonev@gmail.com>
 Yong-Hwan Baek <meisterdevhwan@gmail.com>
 Alexander Khovansky <alx.khovansky@gmail.com>
+Zhuo Qingliang <zhuo.dev@gmail.com>