Use float for scroll offset.

third_party/WebKit/Source/web/tests/RootScrollerTest.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/frame/FrameHost.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/RootFrameViewport.h"
 #include "core/frame/TopControls.h"
 #include "core/html/HTMLFrameOwnerElement.h"
 #include "core/layout/LayoutBox.h"
@@ skipping 190 matching lines @@
     webViewImpl()->handleInputEvent(generateTouchGestureEvent(
         WebInputEvent::GestureScrollUpdate, 0, -topControls().height()));
     EXPECT_FLOAT_EQ(0, topControls().shownRatio());
   }
 
   {
     // Make sure we're actually scrolling the DIV and not the FrameView.
     webViewImpl()->handleInputEvent(
         generateTouchGestureEvent(WebInputEvent::GestureScrollUpdate, 0, -100));
     EXPECT_FLOAT_EQ(100, container->scrollTop());
-    EXPECT_FLOAT_EQ(0, mainFrameView()->scrollPositionDouble().y());
+    EXPECT_FLOAT_EQ(0, mainFrameView()->scrollOffset().height());
   }
 
   {
     // Scroll 50 pixels past the end. Ensure we report the 50 pixels as
     // overscroll.
     EXPECT_CALL(client, didOverscroll(WebFloatSize(0, 50), WebFloatSize(0, 50),
                                       WebFloatPoint(100, 100), WebFloatSize()));
     webViewImpl()->handleInputEvent(
         generateTouchGestureEvent(WebInputEvent::GestureScrollUpdate, 0, -550));
     EXPECT_FLOAT_EQ(maximumScroll, container->scrollTop());
-    EXPECT_FLOAT_EQ(0, mainFrameView()->scrollPositionDouble().y());
+    EXPECT_FLOAT_EQ(0, mainFrameView()->scrollOffset().height());
     Mock::VerifyAndClearExpectations(&client);
   }
 
   {
     // Continue the gesture overscroll.
     EXPECT_CALL(client, didOverscroll(WebFloatSize(0, 20), WebFloatSize(0, 70),
                                       WebFloatPoint(100, 100), WebFloatSize()));
     webViewImpl()->handleInputEvent(
         generateTouchGestureEvent(WebInputEvent::GestureScrollUpdate, 0, -20));
     EXPECT_FLOAT_EQ(maximumScroll, container->scrollTop());
-    EXPECT_FLOAT_EQ(0, mainFrameView()->scrollPositionDouble().y());
+    EXPECT_FLOAT_EQ(0, mainFrameView()->scrollOffset().height());
     Mock::VerifyAndClearExpectations(&client);
   }
 
   webViewImpl()->handleInputEvent(
       generateTouchGestureEvent(WebInputEvent::GestureScrollEnd));
 
   {
     // Make sure a new gesture scroll still won't scroll the frameview and
     // overscrolls.
     webViewImpl()->handleInputEvent(
         generateTouchGestureEvent(WebInputEvent::GestureScrollBegin));
 
     EXPECT_CALL(client, didOverscroll(WebFloatSize(0, 30), WebFloatSize(0, 30),
                                       WebFloatPoint(100, 100), WebFloatSize()));
     webViewImpl()->handleInputEvent(
         generateTouchGestureEvent(WebInputEvent::GestureScrollUpdate, 0, -30));
     EXPECT_FLOAT_EQ(maximumScroll, container->scrollTop());
-    EXPECT_FLOAT_EQ(0, mainFrameView()->scrollPositionDouble().y());
+    EXPECT_FLOAT_EQ(0, mainFrameView()->scrollOffset().height());
     Mock::VerifyAndClearExpectations(&client);
 
     webViewImpl()->handleInputEvent(
         generateTouchGestureEvent(WebInputEvent::GestureScrollEnd));
   }
 
   {
     // Scrolling up should show the top controls.
     webViewImpl()->handleInputEvent(
         generateTouchGestureEvent(WebInputEvent::GestureScrollBegin));
@@ skipping 643 matching lines @@
     mainFrameView()->getRootFrameViewport()->serviceScrollAnimations(0);
 
     EXPECT_EQ(iframe->contentDocument()->documentElement(),
               effectiveRootScroller(iframe->contentDocument()));
   }
 }
 
 }  // namespace
 
 }  // namespace blink