Support offscreen contexts which own their backing surface

third_party/WebKit/Source/platform/RuntimeEnabledFeatures.json5

Index: third_party/WebKit/Source/platform/RuntimeEnabledFeatures.json5
diff --git a/third_party/WebKit/Source/platform/RuntimeEnabledFeatures.json5 b/third_party/WebKit/Source/platform/RuntimeEnabledFeatures.json5
index 5a0b9a2ba4810cfa9322c37a446505220b8a5e2b..2d85b9dce5a98b8b31545019e1075b4f84d698b9 100644
--- a/third_party/WebKit/Source/platform/RuntimeEnabledFeatures.json5
+++ b/third_party/WebKit/Source/platform/RuntimeEnabledFeatures.json5
@@ -911,6 +911,12 @@
       status: "test",
     },
     {
+      name: "WebVRExperimentalRendering",
+      // Don't mark this as depends_on: ["WebVR"], we want to be able to turn
+      // it on for just origin trial sites where the dependency is unset.
+      status: "test",
+    },
+    {
       name: "WebVTTRegions",
       status: "experimental",
     },