[cc/metrics] Delete some dead code

With this CL:
https://chromium-review.googlesource.com/c/chromium/src/+/2234063

We changed how the aggregated throughput is computed, but I forgot
to delete the old old which is the ComputeAggregatedThroughput().

This CL deletes the dead code. This is a code health CL, no
behavior change.

Change-Id: I946e215f10270827065b667893c8782a9482f30a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2285932Reviewed-by: weiliangc <weiliangc@chromium.org>
Commit-Queue: Xida Chen <xidachen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#786431}

cc/metrics/frame_sequence_metrics.cc

@@ -194,17 +194,6 @@ void FrameSequenceMetrics::AdvanceTrace(base::TimeTicks timestamp) {
   trace_data_.Advance(timestamp);
 }
 
-void FrameSequenceMetrics::ComputeAggregatedThroughput() {
-  // Whenever we are expecting and producing main frames, we are expecting and
-  // producing impl frames as well. As an example, if we expect one main frame
-  // to be produced, and when that main frame is presented, we are expecting 3
-  // impl frames, then the number of expected frames is 3 for the aggregated
-  // throughput.
-  aggregated_throughput_.frames_expected = impl_throughput_.frames_expected;
-  DCHECK_LE(aggregated_throughput_.frames_produced,
-            aggregated_throughput_.frames_expected);
-}
-
 void FrameSequenceMetrics::ReportMetrics() {
   DCHECK_LE(impl_throughput_.frames_produced, impl_throughput_.frames_expected);
   DCHECK_LE(main_throughput_.frames_produced, main_throughput_.frames_expected);

cc/metrics/frame_sequence_metrics.h

@@ -106,9 +106,6 @@ class CC_EXPORT FrameSequenceMetrics {
   bool HasDataLeftForReporting() const;
   // Report related metrics: throughput, checkboarding...
   void ReportMetrics();
-  void ComputeAggregatedThroughputForTesting() {
-    ComputeAggregatedThroughput();
-  }
 
   ThroughputData& impl_throughput() { return impl_throughput_; }
   ThroughputData& main_throughput() { return main_throughput_; }
@@ -127,8 +124,6 @@ class CC_EXPORT FrameSequenceMetrics {
   void AdvanceTrace(base::TimeTicks timestamp);
 
  private:
-  void ComputeAggregatedThroughput();
-
   const FrameSequenceTrackerType type_;
 
   // Tracks some data to generate useful trace events.

cc/metrics/frame_sequence_metrics_unittest.cc

@@ -14,18 +14,6 @@
 
 namespace cc {
 
-TEST(FrameSequenceMetricsTest, AggregatedThroughput) {
-  FrameSequenceMetrics first(FrameSequenceTrackerType::kTouchScroll, nullptr);
-  first.impl_throughput().frames_expected = 200u;
-  first.impl_throughput().frames_produced = 190u;
-  first.main_throughput().frames_expected = 100u;
-  first.main_throughput().frames_produced = 50u;
-
-  // The aggregated throughput is computed at ReportMetrics().
-  first.ComputeAggregatedThroughputForTesting();
-  EXPECT_EQ(first.aggregated_throughput().frames_expected, 200u);
-}
-
 TEST(FrameSequenceMetricsTest, AggregatedThroughputClearedAfterReport) {
   FrameSequenceMetrics first(FrameSequenceTrackerType::kCompositorAnimation,
                              nullptr);