Add pixel readback to page popup

Source/web/WebPagePopupImpl.cpp

Index: Source/web/WebPagePopupImpl.cpp
diff --git a/Source/web/WebPagePopupImpl.cpp b/Source/web/WebPagePopupImpl.cpp
index 46728a9bcf44dcfd0d7d6c0fbaf5d5e66b33ce38..ccb487da04cc69f8e5ccb93eafa7d66f6a5e8509 100644
--- a/Source/web/WebPagePopupImpl.cpp
+++ b/Source/web/WebPagePopupImpl.cpp
@@ -44,6 +44,7 @@
 #include "core/page/Page.h"
 #include "core/page/PagePopupClient.h"
 #include "platform/TraceEvent.h"
+#include "public/platform/WebCompositeAndReadbackAsyncCallback.h"
 #include "public/platform/WebCursorInfo.h"
 #include "public/web/WebViewClient.h"
 #include "public/web/WebWidgetClient.h"
@@ -392,6 +393,25 @@ void WebPagePopupImpl::closePopup()
     m_popupClient->didClosePopup();
 }
 
+void WebPagePopupImpl::compositeAndReadbackAsync(WebCompositeAndReadbackAsyncCallback* callback)
+{
+    ASSERT(isAcceleratedCompositingActive());
+    callback->setIsPopup(true);
+    callback->setReadbackPosition(WebPoint(m_windowRectInScreen.x, m_windowRectInScreen.y));
+    m_layerTreeView->compositeAndReadbackAsync(callback);
+}
+
+LocalDOMWindow* WebPagePopupImpl::window()
+{
+    return m_page->mainFrame()->domWindow();
+}
+
+WebPoint WebPagePopupImpl::relativePosition()
+{
+    WebRect windowRect = m_webView->client()->rootWindowRect();
+    return WebPoint(m_windowRectInScreen.x - windowRect.x, m_windowRectInScreen.y - windowRect.y);
+}
+
 // WebPagePopup ----------------------------------------------------------------
 
 WebPagePopup* WebPagePopup::create(WebWidgetClient* client)