Ensure WebView plugins run their lifecycle even absent main frame Layout

third_party/WebKit/Source/core/frame/FrameView.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Dirk Mueller <mueller@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
@@ skipping 62 matching lines @@
 #include "core/loader/FrameLoaderClient.h"
 #include "core/page/AutoscrollController.h"
 #include "core/page/ChromeClient.h"
 #include "core/page/FocusController.h"
 #include "core/page/FrameTree.h"
 #include "core/page/Page.h"
 #include "core/page/scrolling/ScrollingCoordinator.h"
 #include "core/paint/FramePainter.h"
 #include "core/paint/PaintLayer.h"
 #include "core/paint/PaintPropertyTreeBuilder.h"
+#include "core/plugins/PluginView.h"
 #include "core/style/ComputedStyle.h"
 #include "core/svg/SVGDocumentExtensions.h"
 #include "core/svg/SVGSVGElement.h"
 #include "platform/HostWindow.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/ScriptForbiddenScope.h"
 #include "platform/TraceEvent.h"
 #include "platform/TracedValue.h"
 #include "platform/fonts/FontCache.h"
 #include "platform/geometry/DoubleRect.h"
@@ skipping 2522 matching lines @@
     // pointless (since those frames will have set a zero timer to layout anyway), but
     // it is also incorrect, since if two frames overlap, the first could be excluded from the dirty
     // region but then become included later by the second frame adding rects to the dirty region
     // when it lays out.
 
     m_frame->document()->updateLayoutTreeIfNeeded();
 
     if (needsLayout())
         layout();
 
+    // WebView plugins need to update regardless of whether the LayoutEmbeddedObject
+    // that owns them needed layout.

[chrishtr, 2016/02/17 23:49:18]

Add a TODO to fix this in a better way.

+    const ChildrenWidgetSet* viewChildren = children();
+    for (const RefPtrWillBeMember<Widget>& child : *viewChildren) {

[eae, 2016/02/17 23:48:03]

Why is this only needed for WebView plugins and not other widgets? A comment to
that effect would be helpful.

+        if ((*child).isPluginContainer())
+            toPluginView(child.get())->layoutIfNeeded();

[chrishtr, 2016/02/17 23:49:18]

Add a note that this actually runs the entire lifecycle on the plugin.

+    }
+
     // FIXME: Calling layout() shouldn't trigger script execution or have any
     // observable effects on the frame tree but we're not quite there yet.
     WillBeHeapVector<RefPtrWillBeMember<FrameView>> frameViews;
     for (Frame* child = m_frame->tree().firstChild(); child; child = child->tree().nextSibling()) {
         if (!child->isLocalFrame())
             continue;
         if (FrameView* view = toLocalFrame(child)->view())
             frameViews.append(view);
     }
 
@@ skipping 1462 matching lines @@
     return m_hiddenForThrottling && m_crossOriginForThrottling;
 }
 
 LayoutBox& FrameView::boxForScrollControlPaintInvalidation() const
 {
     ASSERT(layoutView());
     return *layoutView();
 }
 
 } // namespace blink