Remove WebLayer::maxScrollPosition().

This code is only used in a test, and cc-side support is going away, so
remove it in Blink.

Review URL: https://codereview.chromium.org/215033003

git-svn-id: svn://svn.chromium.org/blink/trunk@170480 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/web/tests/ScrollingCoordinatorChromiumTest.cpp

@@ -460,7 +460,6 @@ TEST_F(ScrollingCoordinatorChromiumTest, rtlIframe)
 
     int expectedScrollPosition = 958 + (innerFrameView->verticalScrollbar()->isOverlayScrollbar() ? 0 : 15);
     ASSERT_EQ(expectedScrollPosition, webScrollLayer->scrollPosition().x);
-    ASSERT_EQ(expectedScrollPosition, webScrollLayer->maxScrollPosition().width);
 }
 
 TEST_F(ScrollingCoordinatorChromiumTest, setupScrollbarLayerShouldNotCrash)

third_party/WebKit/public/platform/WebLayer.h

@@ -173,8 +173,6 @@ public:
     virtual void setScrollPosition(WebPoint) = 0;
     virtual WebPoint scrollPosition() const = 0;
 
-    virtual WebSize maxScrollPosition() const = 0;
-
     // To set a WebLayer as scrollable we must specify the corresponding clip layer.
     virtual void setScrollClipLayer(WebLayer*) = 0;
     virtual bool scrollable() const = 0;