Move plugins to be stored in HTMLPlugInElement.

third_party/WebKit/Source/core/html/HTMLPlugInElement.cpp

Index: third_party/WebKit/Source/core/html/HTMLPlugInElement.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLPlugInElement.cpp b/third_party/WebKit/Source/core/html/HTMLPlugInElement.cpp
index 9eb65ef0dbf4bb2bf62f5aafb4e2c845cc1624d4..14eb7088831b9db508f123bc84b9c4d3661f28b1 100644
--- a/third_party/WebKit/Source/core/html/HTMLPlugInElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLPlugInElement.cpp
@@ -92,25 +92,55 @@ HTMLPlugInElement::~HTMLPlugInElement() {
 
 DEFINE_TRACE(HTMLPlugInElement) {
   visitor->trace(m_imageLoader);
+  visitor->trace(m_plugin);
   visitor->trace(m_persistedPlugin);
   HTMLFrameOwnerElement::trace(visitor);
 }
 
-// TODO(joelhockey): Move implementation of HTMLFrameOwnerElement
-// setWidget/releaseWidget/ownedWidget that relates to plugins to here and
-// remove inheritance from PluginView to FrameViewBase.
-void HTMLPlugInElement::setPlugin(PluginView* pluginView) {
-  setWidget(pluginView);
-}
+void HTMLPlugInElement::setPlugin(PluginView* plugin) {
+  if (plugin == m_plugin)
+    return;
 
-PluginView* HTMLPlugInElement::releasePlugin() {
-  FrameViewBase* plugin = releaseWidget();
-  return plugin && plugin->isPluginView() ? toPluginView(plugin) : nullptr;
+  // Remove and dispose the old plugin if we had one.
+  if (m_plugin) {
+    document().view()->removePlugin(m_plugin);
+    disposeWidgetSoon(m_plugin);
+  }
+  m_plugin = plugin;
+
+  // TODO(joelhockey): I copied the rest of this method from
+  // HTMLFrameOwnerElement.  There may be parts that can be removed
+  // such as the layoutPartItem.isNull check and DCHECKs.

[dcheng, 2017/04/04 07:20:12]

I feel a bit uneasy about this code duplication. If it mostly ends up looking
similar, can we consider merging them back together?

(I think one of the reasons I'm not entirely comfortable with this change is one
of our goals is get rid of widget trees, and in some ways, we're actually
creating a parallel tree of plugins atm. But maybe that's OK because we're going
to get rid of the original widget tree (m_children) eventually?)

[joelhockey, 2017/04/04 23:39:05]

My primary focus has bene to remove the common base class
(Widget/FrameViewBase).  The primary difference between this method and
HTMLFrameOwnerElement::setWidget is using m_plugins rather than m_children.  So
I agree that I have created something parallel, but technically it is not a
tree.  It is a set of plugins that belong to a frame.  Once I have removed
FrameView::m_children, hopefully a lot of the duplication can go away.  But I
couldn't say right now exactly how it will all turn out.

Again, I don't mind to abandon this CL and maybe I should focus first to remove
m_children.  However everything is all quite tangled and I think it is easier to
remove m_children if I can first pull plugin and scrollbar out.

+  LayoutPart* layoutPart = toLayoutPart(layoutObject());
+  LayoutPartItem layoutPartItem = LayoutPartItem(layoutPart);
+  if (layoutPartItem.isNull())
+    return;
+
+  // Update layout and frame with new plugin.
+  if (m_plugin) {
+    layoutPartItem.updateOnWidgetChange();
+
+    DCHECK_EQ(document().view(), layoutPartItem.frameView());
+    DCHECK(layoutPartItem.frameView());
+    document().view()->addPlugin(plugin);
+  }
+
+  // Apparently accessibility objects might have been modified if plugin
+  // was removed.
+  if (AXObjectCache* cache = document().existingAXObjectCache())
+    cache->childrenChanged(layoutPart);
 }
 
-PluginView* HTMLPlugInElement::ownedPlugin() const {
-  FrameViewBase* plugin = ownedWidget();
-  return plugin && plugin->isPluginView() ? toPluginView(plugin) : nullptr;
+PluginView* HTMLPlugInElement::releasePlugin() {
+  if (!m_plugin)
+    return nullptr;
+  document().view()->removePlugin(m_plugin);
+  LayoutPart* layoutPart = toLayoutPart(layoutObject());
+  if (layoutPart) {
+    if (AXObjectCache* cache = document().existingAXObjectCache())
+      cache->childrenChanged(layoutPart);
+  }
+  return m_plugin.release();
 }
 
 void HTMLPlugInElement::setPersistedPlugin(PluginView* plugin) {
@@ -153,8 +183,7 @@ bool HTMLPlugInElement::requestObjectInternal(
 }
 
 bool HTMLPlugInElement::canProcessDrag() const {
-  return pluginWidget() && pluginWidget()->isPluginView() &&
-         toPluginView(pluginWidget())->canProcessDrag();
+  return pluginWidget() && pluginWidget()->canProcessDrag();
 }
 
 bool HTMLPlugInElement::canStartSelection() const {
@@ -170,9 +199,8 @@ bool HTMLPlugInElement::willRespondToMouseClickEvents() {
 
 void HTMLPlugInElement::removeAllEventListeners() {
   HTMLFrameOwnerElement::removeAllEventListeners();
-  if (LayoutPart* layoutObject = existingLayoutPart()) {
-    if (FrameViewBase* frameViewBase = layoutObject->frameViewBase())
-      frameViewBase->eventListenersRemoved();
+  if (m_plugin) {
+    m_plugin->eventListenersRemoved();
   }
 }
 
@@ -264,7 +292,7 @@ void HTMLPlugInElement::createPluginWithoutLayoutObject() {
 }
 
 bool HTMLPlugInElement::shouldAccelerate() const {
-  return ownedPlugin() && ownedPlugin()->platformLayer();
+  return m_plugin && m_plugin->platformLayer();
 }
 
 void HTMLPlugInElement::detachLayoutTree(const AttachContext& context) {
@@ -280,8 +308,7 @@ void HTMLPlugInElement::detachLayoutTree(const AttachContext& context) {
   }
 
   // Only try to persist a plugin we actually own.
-  PluginView* plugin = ownedPlugin();
-  if (plugin && context.performingReattach) {
+  if (m_plugin && context.performingReattach) {
     setPersistedPlugin(releasePlugin());
   } else {
     // Clear the plugin; will trigger disposal of it with Oilpan.
@@ -347,12 +374,20 @@ SharedPersistent<v8::Object>* HTMLPlugInElement::pluginWrapper() {
   return m_pluginWrapper.get();
 }
 
-FrameViewBase* HTMLPlugInElement::pluginWidget() const {
+// TODO(joelhockey): Remove this and use m_plugin.
+// Maybe just pluginWrapper function should check if m_plugin is null,
+// and call document().updateStyleAndLayoutIgnorePendingStylesheets as per
+// layoutPartForJSBindings.
+PluginView* HTMLPlugInElement::pluginWidget() const {
   if (LayoutPart* layoutPart = layoutPartForJSBindings())
-    return layoutPart->frameViewBase();
+    return layoutPart->plugin();
   return nullptr;
 }
 
+PluginView* HTMLPlugInElement::plugin() const {
+  return m_plugin.get();
+}
+
 bool HTMLPlugInElement::isPresentationAttribute(
     const QualifiedName& name) const {
   if (name == widthAttr || name == heightAttr || name == vspaceAttr ||
@@ -402,10 +437,9 @@ void HTMLPlugInElement::defaultEventHandler(Event* event) {
             .showsUnavailablePluginIndicator())
       return;
   }
-  FrameViewBase* frameViewBase = toLayoutPart(r)->frameViewBase();
-  if (!frameViewBase)
+  if (!m_plugin)
     return;
-  frameViewBase->handleEvent(event);
+  m_plugin->handleEvent(event);
   if (event->defaultHandled())
     return;
   HTMLFrameOwnerElement::defaultEventHandler(event);
@@ -424,8 +458,7 @@ bool HTMLPlugInElement::isKeyboardFocusable() const {
   if (HTMLFrameOwnerElement::isKeyboardFocusable())
     return true;
   return document().isActive() && pluginWidget() &&
-         pluginWidget()->isPluginView() &&
-         toPluginView(pluginWidget())->supportsKeyboardFocus();
+         pluginWidget()->supportsKeyboardFocus();
 }
 
 bool HTMLPlugInElement::hasCustomFocusLogic() const {