Intersection Observer support for OOPIF

third_party/WebKit/Source/web/WebFrameWidgetImpl.cpp

 /*
  * Copyright (C) 2014 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 707 matching lines @@
 // TODO(ekaramad):This method is almost duplicated in WebViewImpl as well. This
 // code needs to be refactored  (http://crbug.com/629721).
 void WebFrameWidgetImpl::applyReplacementRange(const WebRange& range) {
   if (LocalFrame* frame = focusedLocalFrameInWidget()) {
     // TODO(dglazkov): Going from LocalFrame to WebLocalFrameImpl seems
     // silly. What is going on here?
     WebLocalFrameImpl::fromFrame(frame)->selectRange(range);
   }
 }
 
+void WebFrameWidgetImpl::setRemoteViewportIntersection(
+    const WebRect& viewportIntersection) {
+  // Remote viewports are only applicable to local frames with remote ancestors.
+  if (!m_localRoot->parent() || !m_localRoot->parent()->isWebRemoteFrame())

[dcheng, 2017/01/05 07:10:19]

Are these DCHECKable conditions? It seems like we shouldn't be sending the IPC
to begin with if these conditions aren't true.

+    return;
+  if (m_localRoot->frameView()) {

[dcheng, 2017/01/05 07:10:19]

Why would it not have a frame view? IPC races?

[kenrb, 2017/01/09 19:31:20]

Yes, I don't know how to justify these as invariants in cases where an update is
happening concurrently with frame detachment or a swap, for this and the
preceding comment.

+    m_localRoot->frameView()->setViewportIntersectionFromParent(
+        viewportIntersection);
+  }
+}
+
 void WebFrameWidgetImpl::handleMouseLeave(LocalFrame& mainFrame,
                                           const WebMouseEvent& event) {
   // FIXME: WebWidget doesn't have the method below.
   // m_client->setMouseOverURL(WebURL());
   PageWidgetEventHandler::handleMouseLeave(mainFrame, event);
 }
 
 void WebFrameWidgetImpl::handleMouseDown(LocalFrame& mainFrame,
                                          const WebMouseEvent& event) {
   // Take capture on a mouse down on a plugin so we can send it mouse events.
@@ skipping 401 matching lines @@
   return nullptr;
 }
 
 LocalFrame* WebFrameWidgetImpl::focusedLocalFrameAvailableForIme() const {
   if (!m_imeAcceptEvents)
     return nullptr;
   return focusedLocalFrameInWidget();
 }
 
 }  // namespace blink