Check for failed proxy creation in SkDeferredDisplayListRecorder::init

Bug: chromium:227776
Change-Id: I4f628b76aa08c4a3cdc858cd4263a4b6afee7332
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/227837
Auto-Submit: Brian Salomon <bsalomon@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
diff --git a/src/gpu/GrRecordingContext.cpp b/src/gpu/GrRecordingContext.cpp
index cac1492..d007202 100644
--- a/src/gpu/GrRecordingContext.cpp
+++ b/src/gpu/GrRecordingContext.cpp
@@ -151,6 +151,8 @@
         const SkSurfaceProps* props) {
     ASSERT_SINGLE_OWNER_PRIV
 
+    SkASSERT(proxy);
+
     if (proxy->asRenderTargetProxy()) {
         SkASSERT(kPremul_SkAlphaType == alphaType || kOpaque_SkAlphaType == alphaType);
         return this->drawingManager()->makeRenderTargetContext(std::move(proxy), colorType,