Make it possible to set the display mode from the WebView API

Source/core/frame/FrameView.cpp

Index: Source/core/frame/FrameView.cpp
diff --git a/Source/core/frame/FrameView.cpp b/Source/core/frame/FrameView.cpp
index 22c163374628f23f176cb034e5a11a82bb102bda..42ee865ccdf33ad45c7e0e7bdb67005d4cd23efc 100644
--- a/Source/core/frame/FrameView.cpp
+++ b/Source/core/frame/FrameView.cpp
@@ -103,6 +103,7 @@ static const double resourcePriorityUpdateDelayAfterScroll = 0.250;
 
 FrameView::FrameView(LocalFrame* frame)
     : m_frame(frame)
+    , m_displayMode(WebDisplayModeBrowser)
     , m_canHaveScrollbars(true)
     , m_slowRepaintObjectCount(0)
     , m_hasPendingLayout(false)
@@ -1185,6 +1186,12 @@ void FrameView::addPartToUpdate(RenderEmbeddedObject& object)
     m_partUpdateSet.add(&object);
 }
 
+void FrameView::setDisplayMode(WebDisplayMode mode)
+{
+    m_displayMode = mode;
+    m_frame->document()->mediaQueryAffectingValueChanged();
+}
+
 void FrameView::setMediaType(const AtomicString& mediaType)
 {
     ASSERT(m_frame->document());