Plumb site engagement to the renderer process.

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 3635b9b0180081041d5b80f061a2a4a92addb803..2390d2b067a9a57b88d629a0914bba2d3f034889 100644
--- a/third_party/WebKit/Source/core/dom/Document.cpp
+++ b/third_party/WebKit/Source/core/dom/Document.cpp
@@ -491,7 +491,8 @@ Document::Document(const DocumentInit& initializer,
       m_parserSyncPolicy(AllowAsynchronousParsing),
       m_nodeCount(0),
       m_wouldLoadReason(Created),
-      m_passwordCount(0) {
+      m_passwordCount(0),
+      m_engagementLevel(mojom::blink::EngagementLevel::NONE) {
   if (m_frame) {
     DCHECK(m_frame->page());
     provideContextFeaturesToDocumentFrom(*this, *m_frame->page());