Move plugins to be stored in HTMLPlugInElement.

third_party/WebKit/Source/core/page/scrolling/ScrollingCoordinator.cpp

 /*
  * Copyright (C) 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 976 matching lines @@
           scrollableArea->resizerCornerRect(bounds, ResizerForTouch);
       // Map corner to top-frame coords.
       corner = scrollableArea->box()
                    .localToAbsoluteQuad(FloatRect(corner),
                                         TraverseDocumentBoundaries)
                    .enclosingBoundingBox();
       shouldHandleScrollGestureOnMainThreadRegion.unite(corner);
     }
   }
 
-  if (const FrameView::ChildrenSet* children = frameView->children()) {
-    for (const Member<FrameViewBase>& child : *children) {
-      if (!(*child).isPluginView())
-        continue;
-
-      PluginView* pluginView = toPluginView(child.get());
-      if (pluginView->wantsWheelEvents()) {
-        IntRect box = frameView->convertToRootFrame(pluginView->frameRect());
+  if (const FrameView::PluginsSet* plugins = frameView->plugins()) {
+    for (const Member<PluginView>& plugin : *plugins) {
+      if (plugin->wantsWheelEvents()) {
+        IntRect box = frameView->convertToRootFrame(plugin->frameRect());
         shouldHandleScrollGestureOnMainThreadRegion.unite(box);
       }
     }
   }
 
   const FrameTree& tree = frame->tree();
   for (Frame* subFrame = tree.firstChild(); subFrame;
        subFrame = subFrame->tree().nextSibling()) {
     if (subFrame->isLocalFrame()) {
       shouldHandleScrollGestureOnMainThreadRegion.unite(
@@ skipping 178 matching lines @@
           frameView ? toWebLayer(frameView->layoutViewportScrollableArea()
                                      ->layerForScrolling())
                     : nullptr) {
     return WebSize(frameView->layoutViewportScrollableArea()->contentsSize()) !=
            scrollLayer->bounds();
   }
   return false;
 }
 
 }  // namespace blink