FMPDetector: Remove unused timout constants

kNetwork0QuietWindowTimeout and kNetwork2QuietWindowTimeout constants have not used
anywhere since "FMPDetector: Use network quiet signal from IdlenessDetector" commit.

This CL removes them and all uses in FirstMeaningfulPaintDetector.

Bug: 659021,850403
Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_slimming_paint_v2;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: I48c3349d208818ceb8d3cde18fdd7177e310b788
Reviewed-on: https://chromium-review.googlesource.com/1237896Reviewed-by: Kunihiko Sakamoto <ksakamoto@chromium.org>
Reviewed-by: Timothy Dresser <tdresser@chromium.org>
Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
Commit-Queue: Gyuyoung Kim <gyuyoung.kim@lge.com>
Cr-Commit-Position: refs/heads/master@{#594154}

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

@@ -24,9 +24,6 @@ const int kBlankCharactersThreshold = 200;
 
 }  // namespace
 
-constexpr TimeDelta FirstMeaningfulPaintDetector::kNetwork2QuietWindowTimeout;
-constexpr TimeDelta FirstMeaningfulPaintDetector::kNetwork0QuietWindowTimeout;
-
 FirstMeaningfulPaintDetector& FirstMeaningfulPaintDetector::From(
     Document& document) {
   return PaintTiming::From(document).GetFirstMeaningfulPaintDetector();

third_party/blink/renderer/core/paint/first_meaningful_paint_detector.h

@@ -57,13 +57,6 @@ class CORE_EXPORT FirstMeaningfulPaintDetector
     kDeferFirstContentfulPaintNotSet
   };
 
-  // The page is n-quiet if there are no more than n active network requests for
-  // this duration of time.
-  static constexpr TimeDelta kNetwork2QuietWindowTimeout =
-      TimeDelta::FromSecondsD(0.5);
-  static constexpr TimeDelta kNetwork0QuietWindowTimeout =
-      TimeDelta::FromSecondsD(0.5);
-
   Document* GetDocument();
   int ActiveConnections();
   void ReportHistograms();
@@ -80,8 +73,6 @@ class CORE_EXPORT FirstMeaningfulPaintDetector
   TimeTicks provisional_first_meaningful_paint_swap_;
   double max_significance_so_far_ = 0.0;
   double accumulated_significance_while_having_blank_text_ = 0.0;
-  TimeDelta network2_quiet_window_timeout_ = kNetwork2QuietWindowTimeout;
-  TimeDelta network0_quiet_window_timeout_ = kNetwork0QuietWindowTimeout;
   unsigned prev_layout_object_count_ = 0;
   bool seen_first_meaningful_paint_candidate_ = false;
   bool network0_quiet_reached_ = false;

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

@@ -103,13 +103,6 @@ class FirstMeaningfulPaintDetectorTest : public PageTestBase {
  protected:
   ScopedTestingPlatformSupport<TestingPlatformSupportWithMockScheduler>
       platform_;
-
-  TimeDelta GetNetwork0QuietWindowTimeout() {
-    return FirstMeaningfulPaintDetector::kNetwork0QuietWindowTimeout;
-  }
-  TimeDelta GetNetwork2QuietWindowTimeout() {
-    return FirstMeaningfulPaintDetector::kNetwork2QuietWindowTimeout;
-  }
 };
 
 TEST_F(FirstMeaningfulPaintDetectorTest, NoFirstPaint) {