Make it possible to set the display mode from Chromium

content/browser/web_contents/web_contents_impl.cc

Index: content/browser/web_contents/web_contents_impl.cc
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index 8dad3e7904accddb5d06e94501e0e4fc02ede46d..019918bce5b1684c539d22c59bea960ae6b9a053 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -1508,6 +1508,11 @@ bool WebContentsImpl::IsFullscreenForCurrentTab() const {
   return delegate_ ? delegate_->IsFullscreenForTabOrPending(this) : false;
 }
 
+blink::WebDisplayMode WebContentsImpl::GetDisplayMode() const {
+  return delegate_ ? delegate_->GetDisplayMode(this)
+                   : blink::WebDisplayModeBrowser;
+}
+
 void WebContentsImpl::RequestToLockMouse(bool user_gesture,
                                          bool last_unlocked_by_target) {
   if (delegate_) {