Limit lifetime of GrDrawContext objects

src/gpu/GrRenderTarget.cpp

Index: src/gpu/GrRenderTarget.cpp
diff --git a/src/gpu/GrRenderTarget.cpp b/src/gpu/GrRenderTarget.cpp
index 090834912a5540754fc9199214e5223daa308fe4..5cb34e849aa1ed601fe908d7c201066aa554198d 100644
--- a/src/gpu/GrRenderTarget.cpp
+++ b/src/gpu/GrRenderTarget.cpp
@@ -18,7 +18,11 @@
 void GrRenderTarget::discard() {
     // go through context so that all necessary flushing occurs
     GrContext* context = this->getContext();
-    GrDrawContext* drawContext = context ? context->drawContext() : nullptr;
+    if (!context) {
+        return;
+    }
+
+    SkAutoTUnref<GrDrawContext> drawContext(context->drawContext());
     if (!drawContext) {

[jvanverth1, 2015/09/01 14:43:37]

Is this check still needed?

[robertphillips, 2015/09/01 14:49:04]

Yep - the context could still be abandoned at this point (which would return a
NULL draw context).

         return;
     }