Plumb site engagement to the renderer process.

content/renderer/render_frame_impl.cc

Index: content/renderer/render_frame_impl.cc
diff --git a/content/renderer/render_frame_impl.cc b/content/renderer/render_frame_impl.cc
index 00f17b47be2c3ea857ea9936a7d166eba36af23f..a7ec3dccd1818513e14a59cec1e7c9c103cfa7c5 100644
--- a/content/renderer/render_frame_impl.cc
+++ b/content/renderer/render_frame_impl.cc
@@ -1105,6 +1105,7 @@ RenderFrameImpl::RenderFrameImpl(const CreateParams& params)
       focused_pepper_plugin_(nullptr),
       pepper_last_mouse_event_target_(nullptr),
 #endif
+      engagement_binding_(this),
       frame_binding_(this),
       host_zoom_binding_(this),
       has_accessed_initial_document_(false),
@@ -1629,8 +1630,13 @@ void RenderFrameImpl::OnNavigate(
                    std::unique_ptr<StreamOverrideParameters>());
 }
 
-void RenderFrameImpl::Bind(mojom::FrameRequest request,
-                           mojom::FrameHostPtr host) {
+void RenderFrameImpl::BindEngagement(
+    blink::mojom::EngagementClientAssociatedRequest request) {
+  engagement_binding_.Bind(std::move(request));
+}
+
+void RenderFrameImpl::BindFrame(mojom::FrameRequest request,
+                                mojom::FrameHostPtr host) {
   frame_binding_.Bind(std::move(request));
   frame_host_ = std::move(host);
   frame_host_->GetInterfaceProvider(
@@ -2646,6 +2652,26 @@ bool RenderFrameImpl::IsPasting() const {
   return is_pasting_;
 }
 
+// blink::mojom::EngagementClient implementation -------------------------------
+
+void RenderFrameImpl::SetEngagementLevel(const url::Origin& origin,
+                                         blink::mojom::EngagementLevel level) {
+  // Set the engagement level on |frame_| if we have committed the current
+  // navigation. Otherwise, it will be set in didCommitProvisionalLoad.
+  if (frame_ && frame_->dataSource()) {
+    NavigationStateImpl* navigation_state = static_cast<NavigationStateImpl*>(
+        DocumentState::FromDataSource(frame_->dataSource())
+            ->navigation_state());
+    if (navigation_state->request_committed() &&
+        url::Origin(frame_->getSecurityOrigin()) == origin) {
+      frame_->setEngagementLevel(level);
+      return;
+    }

[nasko, 2016/11/30 18:00:25]

This seems like lots of complex logic. Why can't we just simply ask the frame
for the origin of its current security context?

Between always setting the level if the frame current origin matches or saving
it otherwise and always setting it at commit time if found in the map, it should
cover all the cases. Let me know if I've missed some.

[dominickn, 2016/11/30 23:46:33]

I'm definitely not an expert on this (hence the complexity!), so I can't confirm
if this covers all the cases. But I'm more than happy to defer. :)

+  }
+
+  engagement_levels_[origin] = level;

[nasko, 2016/11/30 18:00:25]

Do we need to store the level in the map if it was already set on the frame?

[dominickn, 2016/11/30 23:46:33]

I don't think so - that's why it returns immediately after setting it on the
frame above.

+}
+
 // mojom::Frame implementation -------------------------------------------------
 
 void RenderFrameImpl::GetInterfaceProvider(
@@ -4732,6 +4758,15 @@ void RenderFrameImpl::SendDidCommitProvisionalLoad(
   InternalDocumentStateData* internal_data =
       InternalDocumentStateData::FromDocumentState(document_state);
 
+  // Set the correct engagement level on the frame.
+  EngagementLevels::iterator engagement_level =
+      engagement_levels_.find(url::Origin(GURL(request.url())));

[nasko, 2016/11/30 18:00:25]

Can't we use the frame's origin at this point? Why go through this elaborate
conversion, which actually is lossy too?

[dominickn, 2016/11/30 23:46:33]

Done.

+
+  if (engagement_level != engagement_levels_.end()) {
+    frame_->setEngagementLevel(engagement_level->second);
+    engagement_levels_.erase(engagement_level);

[nasko, 2016/11/30 18:00:25]

The map should never grow big, right? Maybe add some form of a (D)CHECK to
ensure we don't leak? Or alternatively purge the map at commit.

[dominickn, 2016/11/30 23:46:33]

Done - instead of erasing, I just cleared the map immediately after this.

+  }
+
   FrameHostMsg_DidCommitProvisionalLoad_Params params;
   params.http_status_code = response.httpStatusCode();
   params.url_is_unreachable = ds->hasUnreachableURL();
@@ -6484,6 +6519,9 @@ void RenderFrameImpl::HandlePepperImeCommit(const base::string16& text) {
 #endif  // ENABLE_PLUGINS
 
 void RenderFrameImpl::RegisterMojoInterfaces() {
+  GetAssociatedInterfaceRegistry()->AddInterface(
+      base::Bind(&RenderFrameImpl::BindEngagement, weak_factory_.GetWeakPtr()));
+
   if (!frame_->parent()) {
     // Only main frame have ImageDownloader service.
     GetInterfaceRegistry()->AddInterface(base::Bind(