scheduler: Detect load RAIL mode

third_party/WebKit/Source/core/paint/FirstMeaningfulPaintDetectorTest.cpp

 // Copyright 2016 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 "core/paint/FirstMeaningfulPaintDetector.h"
 
 #include "core/paint/PaintTiming.h"
 #include "core/testing/DummyPageHolder.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 71 matching lines @@
 TEST_F(FirstMeaningfulPaintDetectorTest, TwoLayoutsSignificantFirst) {
   paintTiming().markFirstPaint();
   simulateLayoutAndPaint(10);
   double afterLayout1 = monotonicallyIncreasingTime();
   simulateLayoutAndPaint(1);
   simulateNetworkStable();
   EXPECT_GT(paintTiming().firstMeaningfulPaint(), paintTiming().firstPaint());
   EXPECT_LT(paintTiming().firstMeaningfulPaint(), afterLayout1);
 }
 
+TEST_F(FirstMeaningfulPaintDetectorTest, FirstMeaningfulPaintCandidate) {
+  paintTiming().markFirstPaint();
+  EXPECT_EQ(paintTiming().firstMeaningfulPaintCandidate(), 0.0);
+  simulateLayoutAndPaint(1);
+  double afterPaint = monotonicallyIncreasingTime();
+  // The first candidate gets ignored.
+  EXPECT_EQ(paintTiming().firstMeaningfulPaintCandidate(), 0.0);
+  simulateLayoutAndPaint(10);
+  // The second candidate gets reported.
+  EXPECT_GT(paintTiming().firstMeaningfulPaintCandidate(), afterPaint);
+  double candidate = paintTiming().firstMeaningfulPaintCandidate();
+  // The third candidate gets ignored since we already saw the first candidate.
+  simulateLayoutAndPaint(10);
+  EXPECT_EQ(paintTiming().firstMeaningfulPaintCandidate(), candidate);
+}
+
 }  // namespace blink