Lightening fix for UMA metric test failure locally.

third_party/WebKit/Source/core/layout/ScrollAnchorTest.cpp

 // Copyright 2015 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/layout/ScrollAnchor.h"
 
 #include "core/layout/LayoutBox.h"
 #include "core/layout/LayoutTestHelper.h"
 #include "core/paint/PaintLayerScrollableArea.h"
 #include "platform/testing/HistogramTester.h"
@@ skipping 42 matching lines @@
     void scrollLayoutViewport(DoubleSize delta)
     {
         Element* scrollingElement = document().scrollingElement();
         if (delta.width())
             scrollingElement->setScrollTop(scrollingElement->scrollLeft() + delta.width());
         if (delta.height())
             scrollingElement->setScrollTop(scrollingElement->scrollTop() + delta.height());
     }
 };
 
+// TODO(ymalik): Currently, this should be the first test in the file to avoid
+// failure when running with other tests. Dig into this more and fix.
+TEST_F(ScrollAnchorTest, UMAMetricUpdated)
+{
+    HistogramTester histogramTester;
+    setBodyInnerHTML(
+        "<style> body { height: 1000px } div { height: 100px } </style>"
+        "<div id='block1'>abc</div>"
+        "<div id='block2'>def</div>");
+
+    ScrollableArea* viewport = layoutViewport();
+
+    // Scroll position not adjusted, metric not updated.
+    scrollLayoutViewport(DoubleSize(0, 150));
+    histogramTester.expectTotalCount(
+        "Layout.ScrollAnchor.AdjustedScrollOffset", 0);
+
+    // Height changed, verify metric updated once.
+    setHeight(document().getElementById("block1"), 200);
+    histogramTester.expectUniqueSample(
+        "Layout.ScrollAnchor.AdjustedScrollOffset", 1, 1);
+
+    EXPECT_EQ(250, viewport->scrollPosition().y());
+    EXPECT_EQ(document().getElementById("block2")->layoutObject(),
+        scrollAnchor(viewport).anchorObject());
+}
+
 TEST_F(ScrollAnchorTest, Basic)
 {
     setBodyInnerHTML(
         "<style> body { height: 1000px } div { height: 100px } </style>"
         "<div id='block1'>abc</div>"
         "<div id='block2'>def</div>");
 
     ScrollableArea* viewport = layoutViewport();
 
     // No anchor at origin (0,0).
@@ skipping 21 matching lines @@
     ScrollableArea* viewport = layoutViewport();
     scrollLayoutViewport(DoubleSize(0, 100));
 
     document().getElementById("block1")->setAttribute(
         HTMLNames::styleAttr, "height: 50.6px");
     update();
 
     EXPECT_EQ(101, viewport->scrollPosition().y());
 }
 
-TEST_F(ScrollAnchorTest, UMAMetricUpdated)
-{
-    HistogramTester histogramTester;
-    setBodyInnerHTML(
-        "<style> body { height: 1000px } div { height: 100px } </style>"
-        "<div id='block1'>abc</div>"
-        "<div id='block2'>def</div>");
-
-    ScrollableArea* viewport = layoutViewport();
-
-    // Scroll position not adjusted, metric not updated.
-    scrollLayoutViewport(DoubleSize(0, 150));
-    histogramTester.expectTotalCount(
-        "Layout.ScrollAnchor.AdjustedScrollOffset", 0);
-
-    // Height changed, verify metric updated once.
-    setHeight(document().getElementById("block1"), 200);
-    histogramTester.expectUniqueSample(
-        "Layout.ScrollAnchor.AdjustedScrollOffset", 1, 1);
-
-    EXPECT_EQ(250, viewport->scrollPosition().y());
-    EXPECT_EQ(document().getElementById("block2")->layoutObject(),
-        scrollAnchor(viewport).anchorObject());
-}
-
 TEST_F(ScrollAnchorTest, AnchorWithLayerInScrollingDiv)
 {
     setBodyInnerHTML(
         "<style>"
         "    #scroller { overflow: scroll; width: 500px; height: 400px; }"
         "    div { height: 100px }"
         "    #block2 { overflow: hidden }"
         "    #space { height: 1000px; }"
         "</style>"
         "<div id='scroller'><div id='space'>"
@@ skipping 266 matching lines @@
         "<div id=c></div>"
         "<div id=d></div>");
 
     checkCorner("b", Corner::TopRight, DoublePoint(-20,  20),  DoubleSize(0, 0));
     checkCorner("a", Corner::TopRight, DoublePoint(-420, 20),  DoubleSize(400, 0));
     checkCorner("d", Corner::TopRight, DoublePoint(-20,  320), DoubleSize(0, -300));
     checkCorner("c", Corner::TopRight, DoublePoint(-420, 320), DoubleSize(400, -300));
 }
 
 }