[PM] Plumb FirstContentfulPaint to FrameNodes.

This will be used in upcoming page load prioritization logic.

BUG=1064763

Change-Id: I6290b4e500edc39759411f9a00f6f4255e1e0acd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2144312Reviewed-by: Will Harris <wfh@chromium.org>
Reviewed-by: Sigurður Ásgeirsson <siggi@chromium.org>
Reviewed-by: Philip Rogers <pdr@chromium.org>
Commit-Queue: Chris Hamilton <chrisha@chromium.org>
Cr-Commit-Position: refs/heads/master@{#758895}

chrome/browser/ui/webui/discards/graph_dump_impl.h

@@ -92,6 +92,10 @@ class DiscardsGraphDumpImpl : public discards::mojom::GraphDump,
   // Ignored.
   void OnHadFormInteractionChanged(
       const performance_manager::FrameNode* frame_node) override {}
+  // Ignored.
+  void OnFirstContentfulPaint(
+      const performance_manager::FrameNode* frame_node,
+      base::TimeDelta time_since_navigation_start) override {}
 
   // PageNodeObserver implementation:
   void OnPageNodeAdded(const performance_manager::PageNode* page_node) override;

components/performance_manager/graph/frame_node_impl.cc

@@ -87,15 +87,22 @@ void FrameNodeImpl::SetIsAdFrame() {
   is_ad_frame_.SetAndMaybeNotify(this, true);
 }
 
+void FrameNodeImpl::SetHadFormInteraction() {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+  document_.had_form_interaction.SetAndMaybeNotify(this, true);
+}
+
 void FrameNodeImpl::OnNonPersistentNotificationCreated() {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
   for (auto* observer : GetObservers())
     observer->OnNonPersistentNotificationCreated(this);
 }
 
-void FrameNodeImpl::SetHadFormInteraction() {
+void FrameNodeImpl::OnFirstContentfulPaint(
+    base::TimeDelta time_since_navigation_start) {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
-  document_.had_form_interaction.SetAndMaybeNotify(this, true);
+  for (auto* observer : GetObservers())
+    observer->OnFirstContentfulPaint(this, time_since_navigation_start);
 }
 
 const RenderFrameHostProxy& FrameNodeImpl::GetRenderFrameHostProxy() const {

components/performance_manager/graph/frame_node_impl.h

@@ -77,8 +77,10 @@ class FrameNodeImpl
   void SetHasNonEmptyBeforeUnload(bool has_nonempty_beforeunload) override;
   void SetOriginTrialFreezePolicy(mojom::InterventionPolicy policy) override;
   void SetIsAdFrame() override;
-  void OnNonPersistentNotificationCreated() override;
   void SetHadFormInteraction() override;
+  void OnNonPersistentNotificationCreated() override;
+  void OnFirstContentfulPaint(
+      base::TimeDelta time_since_navigation_start) override;
   const RenderFrameHostProxy& GetRenderFrameHostProxy() const override;
 
   // Partial FrameNodbase::TimeDelta time_since_navigatione implementation:

components/performance_manager/graph/frame_node_impl_unittest.cc

@@ -137,10 +137,11 @@ class LenientMockObserver : public FrameNodeImpl::Observer {
   MOCK_METHOD1(OnIsAdFrameChanged, void(const FrameNode*));
   MOCK_METHOD1(OnFrameIsHoldingWebLockChanged, void(const FrameNode*));
   MOCK_METHOD1(OnFrameIsHoldingIndexedDBLockChanged, void(const FrameNode*));
-  MOCK_METHOD1(OnNonPersistentNotificationCreated, void(const FrameNode*));
   MOCK_METHOD2(OnPriorityAndReasonChanged,
                void(const FrameNode*, const PriorityAndReason& previous_value));
   MOCK_METHOD1(OnHadFormInteractionChanged, void(const FrameNode*));
+  MOCK_METHOD1(OnNonPersistentNotificationCreated, void(const FrameNode*));
+  MOCK_METHOD2(OnFirstContentfulPaint, void(const FrameNode*, base::TimeDelta));
 
   void SetCreatedFrameNode(const FrameNode* frame_node) {
     created_frame_node_ = frame_node;
@@ -340,6 +341,21 @@ TEST_F(FrameNodeImplTest, FormInteractions) {
   graph()->RemoveFrameNodeObserver(&obs);
 }
 
+TEST_F(FrameNodeImplTest, FirstContentfulPaint) {
+  auto process = CreateNode<ProcessNodeImpl>();
+  auto page = CreateNode<PageNodeImpl>();
+  auto frame_node = CreateFrameNodeAutoId(process.get(), page.get());
+
+  MockObserver obs;
+  graph()->AddFrameNodeObserver(&obs);
+
+  base::TimeDelta fcp = base::TimeDelta::FromMilliseconds(1364);
+  EXPECT_CALL(obs, OnFirstContentfulPaint(frame_node.get(), fcp));
+  frame_node->OnFirstContentfulPaint(fcp);
+
+  graph()->RemoveFrameNodeObserver(&obs);
+}
+
 TEST_F(FrameNodeImplTest, PublicInterface) {
   auto process = CreateNode<ProcessNodeImpl>();
   auto page = CreateNode<PageNodeImpl>();

components/performance_manager/public/graph/frame_node.h

@@ -230,6 +230,15 @@ class FrameNodeObserver {
   virtual void OnNonPersistentNotificationCreated(
       const FrameNode* frame_node) = 0;
 
+  // Invoked when the frame has had a first contentful paint, as defined here:
+  // https://developers.google.com/web/tools/lighthouse/audits/first-contentful-paint
+  // This may not fire for all frames, depending on if the load is interrupted
+  // or if the content is even visible. It will fire at most once for a given
+  // frame. It will only fire for main-frame nodes.
+  virtual void OnFirstContentfulPaint(
+      const FrameNode* frame_node,
+      base::TimeDelta time_since_navigation_start) = 0;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(FrameNodeObserver);
 };
@@ -263,6 +272,9 @@ class FrameNode::ObserverDefaultImpl : public FrameNodeObserver {
   void OnHadFormInteractionChanged(const FrameNode* frame_node) override {}
   void OnNonPersistentNotificationCreated(
       const FrameNode* frame_node) override {}
+  void OnFirstContentfulPaint(
+      const FrameNode* frame_node,
+      base::TimeDelta time_since_navigation_start) override {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ObserverDefaultImpl);

components/performance_manager/public/mojom/coordination_unit.mojom

@@ -49,7 +49,18 @@ interface DocumentCoordinationUnit {
   SetIsAdFrame();
 
   // Event signals.
+
+  // Called when the associated frame has caused a non-persistent notification
+  // to be created.
   OnNonPersistentNotificationCreated();
+
+  // Invoked when the frame associated with this document has had a first
+  // contentful paint, as defined here:
+  // https://developers.google.com/web/tools/lighthouse/audits/first-contentful-paint
+  // This may not fire for all frames, depending on if the load is interrupted
+  // or if the content is even visible. It will fire at most once for a given
+  // frame. It will only fire for main-frame nodes.
+  OnFirstContentfulPaint(mojo_base.mojom.TimeDelta time_since_navigation_start);
 };
 
 interface ProcessCoordinationUnit {

third_party/blink/renderer/core/paint/paint_timing.cc

@@ -21,6 +21,7 @@
 #include "third_party/blink/renderer/core/timing/dom_window_performance.h"
 #include "third_party/blink/renderer/core/timing/window_performance.h"
 #include "third_party/blink/renderer/platform/instrumentation/histogram.h"
+#include "third_party/blink/renderer/platform/instrumentation/resource_coordinator/document_resource_coordinator.h"
 #include "third_party/blink/renderer/platform/instrumentation/tracing/trace_event.h"
 #include "third_party/blink/renderer/platform/scheduler/public/frame_scheduler.h"
 #include "third_party/blink/renderer/platform/wtf/cross_thread_functional.h"
@@ -245,6 +246,12 @@ void PaintTiming::SetFirstContentfulPaintSwap(base::TimeTicks stamp) {
   if (interactive_detector) {
     interactive_detector->OnFirstContentfulPaint(first_contentful_paint_swap_);
   }
+  auto* coordinator = GetSupplementable()->GetResourceCoordinator();
+  if (coordinator && GetFrame() && GetFrame()->IsMainFrame()) {
+    PerformanceTiming* timing = performance->timing();
+    base::TimeDelta fcp = stamp - timing->NavigationStartAsMonotonicTime();
+    coordinator->OnFirstContentfulPaint(fcp);
+  }
 }
 
 void PaintTiming::SetFirstImagePaintSwap(base::TimeTicks stamp) {

third_party/blink/renderer/platform/instrumentation/resource_coordinator/document_resource_coordinator.cc

@@ -72,4 +72,9 @@ void DocumentResourceCoordinator::SetHadFormInteraction() {
   had_form_interaction_ = true;
 }
 
+void DocumentResourceCoordinator::OnFirstContentfulPaint(
+    base::TimeDelta time_since_navigation_start) {
+  service_->OnFirstContentfulPaint(time_since_navigation_start);
+}
+
 }  // namespace blink

third_party/blink/renderer/platform/instrumentation/resource_coordinator/document_resource_coordinator.h

@@ -35,6 +35,7 @@ class PLATFORM_EXPORT DocumentResourceCoordinator final {
   void SetIsAdFrame();
   void OnNonPersistentNotificationCreated();
   void SetHadFormInteraction();
+  void OnFirstContentfulPaint(base::TimeDelta time_since_navigation_start);
 
  private:
   explicit DocumentResourceCoordinator(const BrowserInterfaceBrokerProxy&);