[Experimental Framework] Make the OriginTrialContext a member of ExecutionContext

third_party/WebKit/Source/core/origin_trials/DocumentOriginTrialContext.h

Index: third_party/WebKit/Source/core/origin_trials/DocumentOriginTrialContext.h
diff --git a/third_party/WebKit/Source/core/origin_trials/DocumentOriginTrialContext.h b/third_party/WebKit/Source/core/origin_trials/DocumentOriginTrialContext.h
new file mode 100644
index 0000000000000000000000000000000000000000..3ea5bc2cc951c91953ea689b070ea0dc9a6f0685
--- /dev/null
+++ b/third_party/WebKit/Source/core/origin_trials/DocumentOriginTrialContext.h
@@ -0,0 +1,39 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef DocumentOriginTrialContext_h
+#define DocumentOriginTrialContext_h
+
+#include "core/CoreExport.h"
+#include "core/dom/Document.h"
+#include "core/origin_trials/OriginTrialContext.h"
+#include "platform/heap/Handle.h"
+#include "wtf/Forward.h"
+#include <utility>
+
+namespace blink {
+
+class WebApiKeyValidator;
+
+// DocumentOriginTrialContext is a specialization of OriginTrialContext for
+// the Document execution context. It enables and disables feature trials based
+// on the tokens found in <meta> tags in the document header.
+class CORE_EXPORT DocumentOriginTrialContext : public OriginTrialContext {
+public:
+    explicit DocumentOriginTrialContext(Document*);
+    ~DocumentOriginTrialContext() override = default;
+
+    ExecutionContext* executionContext() override { return m_parent; }
+
+protected:
+    friend class DocumentOriginTrialContextTest;
+    Vector<String> getTokens() override;
+
+private:
+    RawPtrWillBeWeakPersistent<Document> m_parent;

[sof, 2016/03/01 21:55:21]

Please move DocumentOriginTrialContext to the Oilpan heap rather than use
WeakPersistent<> for a back pointer.

[jbroman, 2016/03/01 23:29:21]

Agreed that WeakPersistent is icky. If Document* is invalid (it's not clear to
me that it should be, if ), then I agree that this should just be a
GarbageCollected object, and can hold a Member<Document> (or
WeakMember<Document>, but IIUC Member is cheaper).

[sof, 2016/03/02 12:36:29]

For an example of owner-ownee w/Oilpan that's near identical to this one, see
VisitedLinkState. 

[iclelland, 2016/03/03 21:47:01]

Done. Moved to heap, replaced this with RawPtrWillBeMember.

+};
+
+} // namespace blink
+
+#endif // DocumentOriginTrialContext_h