Remove ScrollingCoordinator UMA and UKM from the code, and mark as obsolete

The step in LocalFrameView has been merged into CompositingCommit
(PaintArtifactCompositor::Update) in http://crrev.com/815947.

Bug: 1132717
Change-Id: I69417ad86ae3b7507641ad693255aca9e58958ec
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2462068Reviewed-by: Stephen Chenney <schenney@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Robert Kaplow <rkaplow@chromium.org>
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#816648}

cc/metrics/begin_main_frame_metrics.h

@@ -24,7 +24,6 @@ struct CC_EXPORT BeginMainFrameMetrics {
   base::TimeDelta compositing_assignments;
   base::TimeDelta compositing_inputs;
   base::TimeDelta paint;
-  base::TimeDelta scrolling_coordinator;
   base::TimeDelta composite_commit;
   base::TimeDelta update_layers;
   // True if we should measure smoothness in TotalFrameCounter and

cc/metrics/compositor_frame_reporter.cc

@@ -162,9 +162,6 @@ constexpr const char* GetStageName(int stage_type_index,
       return "SendBeginMainFrameToCommit.CompositingAssignments";
     case static_cast<int>(BlinkBreakdown::kPaint) + kBlinkBreakdownInitialIndex:
       return "SendBeginMainFrameToCommit.Paint";
-    case static_cast<int>(BlinkBreakdown::kScrollingCoordinator) +
-        kBlinkBreakdownInitialIndex:
-      return "SendBeginMainFrameToCommit.ScrollingCoordinator";
     case static_cast<int>(BlinkBreakdown::kCompositeCommit) +
         kBlinkBreakdownInitialIndex:
       return "SendBeginMainFrameToCommit.CompositeCommit";
@@ -269,9 +266,9 @@ void ReportOffsetBetweenDeadlineAndPresentationTime(
       static_cast<size_t>(VizBreakdown::kSwapStartToBufferAvailable);          \
   bool has_ready_timings = !!viz_breakdown_list_[start_to_buffer_available];   \
   for (size_t i = 0; i < start_to_buffer_available; i++) {                     \
-    if (!viz_breakdown_list_[i])                                               \
+    if (!viz_breakdown_list_[i]) {                                             \
       break;                                                                   \
-                                                                               \
+    }                                                                          \
     if (i == static_cast<size_t>(VizBreakdown::kSwapStartToSwapEnd) &&         \
         has_ready_timings) {                                                   \
       size_t latch_to_swap_end =                                               \
@@ -999,9 +996,6 @@ void CompositorFrameReporter::PopulateBlinkBreakdownList() {
       blink_breakdown_.compositing_assignments;
   blink_breakdown_list_[static_cast<int>(BlinkBreakdown::kPaint)] =
       blink_breakdown_.paint;
-  blink_breakdown_list_[static_cast<int>(
-      BlinkBreakdown::kScrollingCoordinator)] =
-      blink_breakdown_.scrolling_coordinator;
   blink_breakdown_list_[static_cast<int>(BlinkBreakdown::kCompositeCommit)] =
       blink_breakdown_.composite_commit;
   blink_breakdown_list_[static_cast<int>(BlinkBreakdown::kUpdateLayers)] =

cc/metrics/compositor_frame_reporter.h

@@ -115,10 +115,9 @@ class CC_EXPORT CompositorFrameReporter {
     kCompositingInputs = 5,
     kCompositingAssignments = 6,
     kPaint = 7,
-    kScrollingCoordinator = 8,
-    kCompositeCommit = 9,
-    kUpdateLayers = 10,
-    kBeginMainSentToStarted = 11,
+    kCompositeCommit = 8,
+    kUpdateLayers = 9,
+    kBeginMainSentToStarted = 10,
     kBreakdownCount
   };
 

cc/metrics/compositor_frame_reporter_unittest.cc

@@ -49,20 +49,19 @@ class CompositorFrameReporterTest : public testing::Test {
 
   std::unique_ptr<BeginMainFrameMetrics> BuildBlinkBreakdown() {
     auto breakdown = std::make_unique<BeginMainFrameMetrics>();
-    breakdown->handle_input_events = base::TimeDelta::FromMicroseconds(11);
-    breakdown->animate = base::TimeDelta::FromMicroseconds(10);
-    breakdown->style_update = base::TimeDelta::FromMicroseconds(9);
-    breakdown->layout_update = base::TimeDelta::FromMicroseconds(8);
-    breakdown->compositing_inputs = base::TimeDelta::FromMicroseconds(7);
-    breakdown->prepaint = base::TimeDelta::FromMicroseconds(6);
-    breakdown->compositing_assignments = base::TimeDelta::FromMicroseconds(5);
-    breakdown->paint = base::TimeDelta::FromMicroseconds(4);
-    breakdown->scrolling_coordinator = base::TimeDelta::FromMicroseconds(3);
+    breakdown->handle_input_events = base::TimeDelta::FromMicroseconds(10);
+    breakdown->animate = base::TimeDelta::FromMicroseconds(9);
+    breakdown->style_update = base::TimeDelta::FromMicroseconds(8);
+    breakdown->layout_update = base::TimeDelta::FromMicroseconds(7);
+    breakdown->compositing_inputs = base::TimeDelta::FromMicroseconds(6);
+    breakdown->prepaint = base::TimeDelta::FromMicroseconds(5);
+    breakdown->compositing_assignments = base::TimeDelta::FromMicroseconds(4);
+    breakdown->paint = base::TimeDelta::FromMicroseconds(3);
     breakdown->composite_commit = base::TimeDelta::FromMicroseconds(2);
     breakdown->update_layers = base::TimeDelta::FromMicroseconds(1);
 
     // Advance now by the sum of the breakdowns.
-    AdvanceNowByMs(11 + 10 + 9 + 8 + 7 + 6 + 5 + 4 + 3 + 2 + 1);
+    AdvanceNowByMs(10 + 9 + 8 + 7 + 6 + 5 + 4 + 3 + 2 + 1);
 
     return breakdown;
   }
@@ -376,9 +375,6 @@ TEST_F(CompositorFrameReporterTest,
        blink_breakdown_copy.compositing_assignments},
       {"EventLatency.TouchPressed.SendBeginMainFrameToCommit.Paint",
        blink_breakdown_copy.paint},
-      {"EventLatency.TouchPressed.SendBeginMainFrameToCommit."
-       "ScrollingCoordinator",
-       blink_breakdown_copy.scrolling_coordinator},
       {"EventLatency.TouchPressed.SendBeginMainFrameToCommit.CompositeCommit",
        blink_breakdown_copy.composite_commit},
       {"EventLatency.TouchPressed.SendBeginMainFrameToCommit.UpdateLayers",

cc/metrics/compositor_frame_reporting_controller_unittest.cc

@@ -144,20 +144,19 @@ class CompositorFrameReportingControllerTest : public testing::Test {
 
   std::unique_ptr<BeginMainFrameMetrics> BuildBlinkBreakdown() {
     auto breakdown = std::make_unique<BeginMainFrameMetrics>();
-    breakdown->handle_input_events = base::TimeDelta::FromMicroseconds(11);
-    breakdown->animate = base::TimeDelta::FromMicroseconds(10);
-    breakdown->style_update = base::TimeDelta::FromMicroseconds(9);
-    breakdown->layout_update = base::TimeDelta::FromMicroseconds(8);
-    breakdown->compositing_inputs = base::TimeDelta::FromMicroseconds(7);
-    breakdown->prepaint = base::TimeDelta::FromMicroseconds(6);
-    breakdown->compositing_assignments = base::TimeDelta::FromMicroseconds(5);
-    breakdown->paint = base::TimeDelta::FromMicroseconds(4);
-    breakdown->scrolling_coordinator = base::TimeDelta::FromMicroseconds(3);
+    breakdown->handle_input_events = base::TimeDelta::FromMicroseconds(10);
+    breakdown->animate = base::TimeDelta::FromMicroseconds(9);
+    breakdown->style_update = base::TimeDelta::FromMicroseconds(8);
+    breakdown->layout_update = base::TimeDelta::FromMicroseconds(7);
+    breakdown->compositing_inputs = base::TimeDelta::FromMicroseconds(6);
+    breakdown->prepaint = base::TimeDelta::FromMicroseconds(5);
+    breakdown->compositing_assignments = base::TimeDelta::FromMicroseconds(4);
+    breakdown->paint = base::TimeDelta::FromMicroseconds(3);
     breakdown->composite_commit = base::TimeDelta::FromMicroseconds(2);
     breakdown->update_layers = base::TimeDelta::FromMicroseconds(1);
 
     // Advance now by the sum of the breakdowns.
-    AdvanceNowByMs(11 + 10 + 9 + 8 + 7 + 6 + 5 + 4 + 3 + 2 + 1);
+    AdvanceNowByMs(10 + 9 + 8 + 7 + 6 + 5 + 4 + 3 + 2 + 1);
 
     return breakdown;
   }
@@ -921,18 +920,15 @@ TEST_F(CompositorFrameReportingControllerTest, BlinkBreakdown) {
       base::TimeDelta::FromMicroseconds(7).InMilliseconds(), 1);
   histogram_tester.ExpectUniqueSample(
       "CompositorLatency.SendBeginMainFrameToCommit.CompositingInputs",
-      base::TimeDelta::FromMicroseconds(5).InMilliseconds(), 1);
-  histogram_tester.ExpectUniqueSample(
-      "CompositorLatency.SendBeginMainFrameToCommit.Prepaint",
       base::TimeDelta::FromMicroseconds(6).InMilliseconds(), 1);
   histogram_tester.ExpectUniqueSample(
-      "CompositorLatency.SendBeginMainFrameToCommit.CompositingAssignments",
+      "CompositorLatency.SendBeginMainFrameToCommit.Prepaint",
       base::TimeDelta::FromMicroseconds(5).InMilliseconds(), 1);
   histogram_tester.ExpectUniqueSample(
-      "CompositorLatency.SendBeginMainFrameToCommit.Paint",
+      "CompositorLatency.SendBeginMainFrameToCommit.CompositingAssignments",
       base::TimeDelta::FromMicroseconds(4).InMilliseconds(), 1);
   histogram_tester.ExpectUniqueSample(
-      "CompositorLatency.SendBeginMainFrameToCommit.ScrollingCoordinator",
+      "CompositorLatency.SendBeginMainFrameToCommit.Paint",
       base::TimeDelta::FromMicroseconds(3).InMilliseconds(), 1);
   histogram_tester.ExpectUniqueSample(
       "CompositorLatency.SendBeginMainFrameToCommit.CompositeCommit",
@@ -1153,9 +1149,6 @@ TEST_F(CompositorFrameReportingControllerTest,
        blink_breakdown_copy.compositing_assignments},
       {"EventLatency.TouchPressed.SendBeginMainFrameToCommit.Paint",
        blink_breakdown_copy.paint},
-      {"EventLatency.TouchPressed.SendBeginMainFrameToCommit."
-       "ScrollingCoordinator",
-       blink_breakdown_copy.scrolling_coordinator},
       {"EventLatency.TouchPressed.SendBeginMainFrameToCommit.CompositeCommit",
        blink_breakdown_copy.composite_commit},
       {"EventLatency.TouchPressed.SendBeginMainFrameToCommit.UpdateLayers",

third_party/blink/renderer/core/frame/local_frame_ukm_aggregator.cc

@@ -195,10 +195,6 @@ LocalFrameUkmAggregator::GetBeginMainFrameMetrics() {
   metrics_data->paint =
       main_frame_percentage_records_[static_cast<unsigned>(MetricId::kPaint)]
           .interval_duration;
-  metrics_data->scrolling_coordinator =
-      main_frame_percentage_records_[static_cast<unsigned>(
-                                         MetricId::kScrollingCoordinator)]
-          .interval_duration;
   metrics_data->composite_commit =
       main_frame_percentage_records_[static_cast<unsigned>(
                                          MetricId::kCompositingCommit)]
@@ -431,7 +427,6 @@ void LocalFrameUkmAggregator::ReportPreFCPEvent() {
       CASE_FOR_ID(Layout);
       CASE_FOR_ID(ForcedStyleAndLayout);
       CASE_FOR_ID(HitTestDocumentUpdate);
-      CASE_FOR_ID(ScrollingCoordinator);
       CASE_FOR_ID(HandleInputEvents);
       CASE_FOR_ID(Animate);
       CASE_FOR_ID(UpdateLayers);
@@ -477,7 +472,6 @@ void LocalFrameUkmAggregator::ReportUpdateTimeEvent() {
       CASE_FOR_ID(Layout, i);
       CASE_FOR_ID(ForcedStyleAndLayout, i);
       CASE_FOR_ID(HitTestDocumentUpdate, i);
-      CASE_FOR_ID(ScrollingCoordinator, i);
       CASE_FOR_ID(HandleInputEvents, i);
       CASE_FOR_ID(Animate, i);
       CASE_FOR_ID(UpdateLayers, i);

third_party/blink/renderer/core/frame/local_frame_ukm_aggregator.h

@@ -125,8 +125,8 @@ class CORE_EXPORT LocalFrameUkmAggregator
     : public RefCounted<LocalFrameUkmAggregator> {
  public:
   // Changing these values requires changing the names of metrics specified
-  // below. For every metric name added here, add an entry in the
-  // metric_strings_ array below.
+  // below. For every metric name added here, add an entry in the array in
+  // metrics_data() below.
   enum MetricId {
     kCompositingAssignments,
     kCompositingCommit,
@@ -139,7 +139,6 @@ class CORE_EXPORT LocalFrameUkmAggregator
     kLayout,
     kForcedStyleAndLayout,
     kHitTestDocumentUpdate,
-    kScrollingCoordinator,
     kHandleInputEvents,
     kAnimate,
     kUpdateLayers,
@@ -173,7 +172,6 @@ class CORE_EXPORT LocalFrameUkmAggregator
         {"Layout", true},
         {"ForcedStyleAndLayout", true},
         {"HitTestDocumentUpdate", true},
-        {"ScrollingCoordinator", true},
         {"HandleInputEvents", true},
         {"Animate", true},
         {"UpdateLayers", false},

third_party/blink/renderer/core/frame/local_frame_ukm_aggregator_test.cc

@@ -308,8 +308,6 @@ TEST_F(LocalFrameUkmAggregatorTest, LatencyDataIsPopulated) {
   EXPECT_EQ(metrics_data->compositing_assignments.InMillisecondsF(),
             millisecond_for_step);
   EXPECT_EQ(metrics_data->paint.InMillisecondsF(), millisecond_for_step);
-  EXPECT_EQ(metrics_data->scrolling_coordinator.InMillisecondsF(),
-            millisecond_for_step);
   EXPECT_EQ(metrics_data->composite_commit.InMillisecondsF(),
             millisecond_for_step);
   // Do not check the value in metrics_data.update_layers because it

tools/metrics/histograms/histograms_xml/blink/histograms.xml

@@ -1316,7 +1316,11 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 </histogram>
 
 <histogram base="true" name="Blink.MainFrame.ScrollingCoordinatorRatio"
-    units="%" expires_after="2020-11-08">
+    units="%" expires_after="M88">
+  <obsolete>
+    Merged into Blink.MainFrame.CompositingCommitRatio in
+    http://crrev.com/815947 in M88.
+  </obsolete>
   <owner>schenney@chromium.org</owner>
   <owner>paint-dev@chromium.org</owner>
 <!-- Name completed by histogram_suffixes name="BlinkMainFrameUpdateTimeSuffixes" -->
@@ -1638,7 +1642,11 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 </histogram>
 
 <histogram name="Blink.ScrollingCoordinator.UpdateTime" units="microseconds"
-    expires_after="2021-03-21">
+    expires_after="M88">
+  <obsolete>
+    Merged into Blink.CompositingCommit.UpdateTime in http://crrev.com/815947 in
+    M88.
+  </obsolete>
 <!-- Name completed by histogram_suffixes name="BlinkUpdateTimePreFCPSuffixes" -->
 
 <!-- Name completed by histogram_suffixes name="BlinkUpdateTimePostFCPSuffixes" -->

tools/metrics/ukm/ukm.xml

@@ -2027,6 +2027,9 @@ be describing additional metrics about the same event.
     </summary>
   </metric>
   <metric name="ScrollingCoordinator">
+    <obsolete>
+      Merged into CompositingCommit in http://crrev.com/815947 in M88.
+    </obsolete>
     <summary>
       The time spent in ScrollingCoordinator, between navigation and First
       Contentful Paint, in microseconds.
@@ -2819,6 +2822,9 @@ be describing additional metrics about the same event.
     </summary>
   </metric>
   <metric name="ScrollingCoordinator">
+    <obsolete>
+      Merged into CompositingCommit in http://crrev.com/815947 in M88.
+    </obsolete>
     <summary>
       The time taken for scrolling coordinator for the main frame in
       microseconds during the sampled frame.
@@ -2879,6 +2885,9 @@ be describing additional metrics about the same event.
     </summary>
   </metric>
   <metric name="ScrollingCoordinatorPercentage">
+    <obsolete>
+      Merged into CompositingCommitPercentage in http://crrev.com/815947 in M88.
+    </obsolete>
     <summary>
       The percentage of the main frame time used in scrolling coordinator. An
       int in the range [0,100].