Plumb site engagement to the renderer process.

chrome/browser/engagement/site_engagement_helper.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/engagement/site_engagement_helper.h"
 
 #include <utility>
 
+#include "base/bind.h"
+#include "base/callback.h"
 #include "base/time/time.h"
 #include "base/trace_event/trace_event.h"
 #include "chrome/browser/engagement/site_engagement_service.h"
 #include "chrome/browser/prerender/prerender_contents.h"
 #include "chrome/browser/profiles/profile.h"
 #include "content/public/browser/navigation_handle.h"
+#include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/web_contents.h"
+#include "content/public/common/associated_interface_provider.h"
+#include "url/gurl.h"
+#include "url/origin.h"
 
 namespace {
 
 int g_seconds_to_pause_engagement_detection = 10;
 int g_seconds_delay_after_navigation = 10;
 int g_seconds_delay_after_media_starts = 10;
 int g_seconds_delay_after_show = 5;
 
 }  // anonymous namespace
 
 DEFINE_WEB_CONTENTS_USER_DATA_KEY(SiteEngagementService::Helper);
 
+// static
+void SiteEngagementService::Helper::SetSecondsBetweenUserInputCheck(
+    int seconds) {
+  g_seconds_to_pause_engagement_detection = seconds;
+}
+
+// static
+void SiteEngagementService::Helper::SetSecondsTrackingDelayAfterNavigation(
+    int seconds) {
+  g_seconds_delay_after_navigation = seconds;
+}
+
+// static
+void SiteEngagementService::Helper::SetSecondsTrackingDelayAfterShow(
+    int seconds) {
+  g_seconds_delay_after_show = seconds;
+}
+
+SiteEngagementService::Helper::~Helper() {
+  service_->HelperDeleted(this);
+  if (web_contents()) {
+    input_tracker_.Stop();
+    media_tracker_.Stop();
+  }
+}
+
+void SiteEngagementService::Helper::OnEngagementLevelChanged(
+    const GURL& url,
+    blink::mojom::EngagementLevel level) {
+  web_contents()->ForEachFrame(base::Bind(
+      &SiteEngagementService::Helper::SendEngagementLevelToFramesMatchingOrigin,

[dcheng, 2016/12/08 08:14:07]

It almost feels a bit wasteful to do this... all the frames matching an origin
should be in the same process. Maybe it doesn't matter, since this is
conceptually simpler though.

[dominickn, 2016/12/08 09:02:47]

Yeah, I did it this way to be as simple (and robust) as possible.

+      base::Unretained(this), url::Origin(url), level));
+}
+
 SiteEngagementService::Helper::PeriodicTracker::PeriodicTracker(
     SiteEngagementService::Helper* helper)
     : helper_(helper), pause_timer_(new base::Timer(true, false)) {}
 
 SiteEngagementService::Helper::PeriodicTracker::~PeriodicTracker() {}
 
 void SiteEngagementService::Helper::PeriodicTracker::Start(
     base::TimeDelta initial_delay) {
   StartTimer(initial_delay);
 }
@@ skipping 112 matching lines @@
 }
 
 void SiteEngagementService::Helper::MediaTracker::WasShown() {
   is_hidden_ = false;
 }
 
 void SiteEngagementService::Helper::MediaTracker::WasHidden() {
   is_hidden_ = true;
 }
 
-SiteEngagementService::Helper::~Helper() {
-  if (web_contents()) {
-    input_tracker_.Stop();
-    media_tracker_.Stop();
-  }
-}
-
 SiteEngagementService::Helper::Helper(content::WebContents* web_contents)
     : content::WebContentsObserver(web_contents),
       input_tracker_(this, web_contents),
       media_tracker_(this, web_contents),
       service_(SiteEngagementService::Get(
-          Profile::FromBrowserContext(web_contents->GetBrowserContext()))) {}
+          Profile::FromBrowserContext(web_contents->GetBrowserContext()))) {
+  service_->HelperCreated(this);
+}
 
 void SiteEngagementService::Helper::RecordUserInput(
     SiteEngagementMetrics::EngagementType type) {
   TRACE_EVENT0("SiteEngagement", "RecordUserInput");
   content::WebContents* contents = web_contents();
   if (contents)
     service_->HandleUserInput(contents, type);
 }
 
 void SiteEngagementService::Helper::RecordMediaPlaying(bool is_hidden) {
   content::WebContents* contents = web_contents();
   if (contents)
     service_->HandleMediaPlaying(contents, is_hidden);
 }
 
+void SiteEngagementService::Helper::SendEngagementLevelToFramesMatchingOrigin(
+    const url::Origin& origin,
+    blink::mojom::EngagementLevel level,
+    content::RenderFrameHost* render_frame_host) {
+  if (origin == render_frame_host->GetLastCommittedOrigin()) {
+    SendEngagementLevelToFrame(origin, level, render_frame_host);
+  }
+}
+
+void SiteEngagementService::Helper::SendEngagementLevelToFrame(
+    const url::Origin& origin,
+    blink::mojom::EngagementLevel level,
+    content::RenderFrameHost* render_frame_host) {
+  blink::mojom::EngagementClientAssociatedPtr client;
+  render_frame_host->GetRemoteAssociatedInterfaces()->GetInterface(&client);
+  client->SetEngagementLevel(origin, level);
+}
+
 void SiteEngagementService::Helper::DidFinishNavigation(
     content::NavigationHandle* handle) {
   // Ignore uncommitted, non main-frame, same page, or error page navigations.
   if (!handle->HasCommitted() || !handle->IsInMainFrame() ||
       handle->IsSamePage() || handle->IsErrorPage()) {
     return;
   }
 
   input_tracker_.Stop();
   media_tracker_.Stop();
@@ skipping 13 matching lines @@
   // will activate even if navigation engagement is not scored.
   if (prerender::PrerenderContents::FromWebContents(web_contents()) != nullptr)
     return;
 
   service_->HandleNavigation(web_contents(), handle->GetPageTransition());
 
   input_tracker_.Start(
       base::TimeDelta::FromSeconds(g_seconds_delay_after_navigation));
 }
 
+void SiteEngagementService::Helper::ReadyToCommitNavigation(
+    content::NavigationHandle* handle) {
+  GURL url = handle->GetURL();

[dcheng, 2016/12/08 08:14:07]

Nit: avoid making a copy here and just call url::Origin(handle->GetURL())

Also, how does this work for things like data URLs?

[dcheng, 2016/12/08 08:14:45]

(or filesystem: or blob: urls)

[dominickn, 2016/12/08 09:02:47]

Done.

Only HTTP/HTTPS URLs earn engagement, so blobs/file/data URLs will just send
NONE down to the renderer. I've added a small optimisation to avoid the
extraneous IPC here because NONE is the default value on Document.

+  SendEngagementLevelToFrame(url::Origin(url),
+                             service_->GetEngagementLevel(url),
+                             handle->GetRenderFrameHost());
+}
+
 void SiteEngagementService::Helper::WasShown() {
   // Ensure that the input callbacks are registered when we come into view.
   input_tracker_.Start(
       base::TimeDelta::FromSeconds(g_seconds_delay_after_show));
 }
 
 void SiteEngagementService::Helper::WasHidden() {
   // Ensure that the input callbacks are not registered when hidden.
   input_tracker_.Stop();
 }
-
-// static
-void SiteEngagementService::Helper::SetSecondsBetweenUserInputCheck(
-    int seconds) {
-  g_seconds_to_pause_engagement_detection = seconds;
-}
-
-// static
-void SiteEngagementService::Helper::SetSecondsTrackingDelayAfterNavigation(
-    int seconds) {
-  g_seconds_delay_after_navigation = seconds;
-}
-
-// static
-void SiteEngagementService::Helper::SetSecondsTrackingDelayAfterShow(
-    int seconds) {
-  g_seconds_delay_after_show = seconds;
-}