Move the logic to retrieve the WebPluginContainer to LocalFrame and Node.

third_party/WebKit/Source/core/frame/LocalFrame.h

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999-2001 Lars Knoll <knoll@kde.org>
  *                     1999-2001 Antti Koivisto <koivisto@kde.org>
  *                     2000-2001 Simon Hausmann <hausmann@kde.org>
  *                     2000-2001 Dirk Mueller <mueller@kde.org>
  *                     2000 Stefan Schimanski <1Stein@gmx.de>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights
  * reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
@@ skipping 63 matching lines @@
 class NavigationScheduler;
 class Node;
 class NodeTraversal;
 class PerformanceMonitor;
 template <typename Strategy>
 class PositionWithAffinityTemplate;
 class PluginData;
 class ScriptController;
 class SpellChecker;
 class WebFrameScheduler;
+class WebPluginContainerBase;
 class WebURLLoader;
 
 extern template class CORE_EXTERN_TEMPLATE_EXPORT Supplement<LocalFrame>;
 
 class CORE_EXPORT LocalFrame final : public Frame,
                                      public Supplementable<LocalFrame> {
   USING_GARBAGE_COLLECTED_MIXIN(LocalFrame);
 
   friend class LocalFrameTest;
 
@@ skipping 143 matching lines @@
 
   std::unique_ptr<WebURLLoader> CreateURLLoader();
 
   using FrameInitCallback = void (*)(LocalFrame*);
   // Allows for the registration of a callback that is invoked whenever a new
   // LocalFrame is initialized. Callbacks are executed in the order that they
   // were added using registerInitializationCallback, and there are no checks
   // for adding a callback multiple times.
   static void RegisterInitializationCallback(FrameInitCallback);
 
+  // If the frame hosts a PluginDocument, this method returns the
+  // WebPluginContainerBase that hosts the plugin. If the provided node is a
+  // plugin, then it returns its WebPluginContainerBase. Otherwise, uses the
+  // currently focused element (if any).

[haraken, 2017/05/22 04:51:44]

This looks like a weird semantics. Can we drop the part after "If the provided
node..." in a follow-up CL?

Alternately we can just make the caller site to query the focused element and
call Node::GetWebPluginContainerBase when LocalFrame::GetWebPluginContainerBase
returns nullptr. It looks weird to hide the logic in
LocalFrame::GetWebPluginContainerBase.

[dcheng, 2017/05/22 09:48:29]

I agree it's a bit confusing (which is why I was hoping we didn't have to plumb
a Node in at all). But I'm not sure if making current callsites explicitly grab
the focused node is better as it's called in a fair number of different places.

[slangley, 2017/05/22 23:53:25]

I added a TODO and will followup with a CL to address this.

+  WebPluginContainerBase* GetWebPluginContainerBase(Node* = nullptr) const;
+
  private:
   friend class FrameNavigationDisabler;
 
   LocalFrame(LocalFrameClient*,
              Page&,
              FrameOwner*,
              InterfaceProvider*,
              InterfaceRegistry*);
 
   // Intentionally private to prevent redundant checks when the type is
@@ skipping 129 matching lines @@
   explicit ScopedFrameBlamer(LocalFrame*);
   ~ScopedFrameBlamer();
 
  private:
   Member<LocalFrame> frame_;
 };
 
 }  // namespace blink
 
 #endif  // LocalFrame_h