Merge remote-tracking branch 'origin/5.5' into 5.6

Conflicts:
	src/webenginewidgets/render_widget_host_view_qt_delegate_widget.cpp

Change-Id: I451bc61673014db8e87b2a2cf98fb6879ce0e58d

1 files changed, 6 insertions, 0 deletions

diff --git a/src/webenginewidgets/render_widget_host_view_qt_delegate_widget.cpp b/src/webenginewidgets/render_widget_host_view_qt_delegate_widget.cpp
index 57631c4cc..9871ecfb1 100644
--- a/src/webenginewidgets/render_widget_host_view_qt_delegate_widget.cpp
+++ b/src/webenginewidgets/render_widget_host_view_qt_delegate_widget.cpp
@@ -290,6 +290,12 @@ void RenderWidgetHostViewQtDelegateWidget::initializeGL()
     m_sgRenderer.reset(m_sgEngine->createRenderer());
     m_sgRenderer->setRootNode(m_rootNode.data());
     m_sgRenderer->setClearColor(m_clearColor);
+
+    // When RenderWidgetHostViewQt::GetScreenInfo is called for the first time, the associated
+    // QWindow is NULL, and the screen device pixel ratio can not be queried.
+    // Re-initialize the screen information after the QWindow handle is available,
+    // so Chromium receives the correct device pixel ratio.
+    m_client->windowChanged();
 }
 
 void RenderWidgetHostViewQtDelegateWidget::paintGL()