Visual viewport API initial implementation.

third_party/WebKit/Source/core/dom/Document.cpp

Index: third_party/WebKit/Source/core/dom/Document.cpp
diff --git a/third_party/WebKit/Source/core/dom/Document.cpp b/third_party/WebKit/Source/core/dom/Document.cpp
index dae347c7eed3cb2beeaa3708f6564629b8a72db9..f1a072521f86e05d87fbfd27d910ce2a7e1e50c6 100644
--- a/third_party/WebKit/Source/core/dom/Document.cpp
+++ b/third_party/WebKit/Source/core/dom/Document.cpp
@@ -1230,6 +1230,13 @@ Element* Document::scrollingElement()
     return body();
 }
 
+VisualViewport* Document::visualViewport()
+{
+    if (FrameHost* host = frameHost())
+        return &host->visualViewport();
+    return nullptr;
+}
+
 /*
  * Performs three operations:
  *  1. Convert control characters to spaces
@@ -4018,6 +4025,13 @@ void Document::enqueueMediaQueryChangeListeners(HeapVector<Member<MediaQueryList
     ensureScriptedAnimationController().enqueueMediaQueryChangeListeners(listeners);
 }
 
+void Document::enqueueVisualViewportChangedEvent()
+{
+    RawPtr<Event> event = Event::create(EventTypeNames::visualviewportchanged);
+    event->setTarget(this);
+    ensureScriptedAnimationController().enqueuePerFrameEvent(event.release());
+}
+
 void Document::dispatchEventsForPrinting()
 {
     if (!m_scriptedAnimationController)