ScrollableArea::pixelStep should return DIP not viewport (physical pixels)

third_party/WebKit/LayoutTests/TestExpectations

Index: third_party/WebKit/LayoutTests/TestExpectations
diff --git a/third_party/WebKit/LayoutTests/TestExpectations b/third_party/WebKit/LayoutTests/TestExpectations
index 69c1af35818d83889404940d9d4641d6f48605bd..9cece100deed5c3b8be0bd1aa9da47c005e81af9 100644
--- a/third_party/WebKit/LayoutTests/TestExpectations
+++ b/third_party/WebKit/LayoutTests/TestExpectations
@@ -282,6 +282,12 @@ crbug.com/495750 [ Mac Android ] virtual/scalefactor200withzoom/fast/hidpi/stati
 # TODO(oshima): Fix the popup's size adjustmenet.
 crbug.com/495750 [ Mac ] virtual/scalefactor200withzoom/fast/hidpi/static/data-suggestion-picker-appearance.html [ Skip ]
 
+# TODO(oshima): Move the event scaling code to eventSender and remove this.
+crbug.com/495750 virtual/scalefactor200/fast/hidpi/static/mousewheel-scroll-amount.html [ Skip ]
+crbug.com/495750 virtual/scalefactor200/fast/hidpi/static/gesture-scroll-amount.html [ Skip ]
+crbug.com/495750 virtual/scalefactor150/fast/hidpi/static/mousewheel-scroll-amount.html [ Skip ]
+crbug.com/495750 virtual/scalefactor150/fast/hidpi/static/gesture-scroll-amount.html [ Skip ]
+
 # TODO(ojan): These tests aren't flaky. See crbug.com/517144.
 # Release trybots run asserts, but the main waterfall ones don't. So, even
 # though this is a non-flaky assert failure, we need to mark it [ Pass Crash ].