Scroll offset pinning and content size notifications were only used for the Mac overlay navigation …

content/browser/renderer_host/render_widget_host_view_mac.mm

Index: content/browser/renderer_host/render_widget_host_view_mac.mm
diff --git a/content/browser/renderer_host/render_widget_host_view_mac.mm b/content/browser/renderer_host/render_widget_host_view_mac.mm
index b6a62124b8de499a2562d975c27b5a64f8dd8a6d..4db85a70454986feb80c031eb42d69f045b56913 100644
--- a/content/browser/renderer_host/render_widget_host_view_mac.mm
+++ b/content/browser/renderer_host/render_widget_host_view_mac.mm
@@ -142,8 +142,6 @@ static BOOL SupportsBackingPropertiesChangedNotification() {
 - (void)processedWheelEvent:(const blink::WebMouseWheelEvent&)event
                    consumed:(BOOL)consumed;
 
-- (void)scrollOffsetPinnedToLeft:(BOOL)left toRight:(BOOL)right;
-- (void)setHasHorizontalScrollbar:(BOOL)has_horizontal_scrollbar;
 - (void)keyEvent:(NSEvent*)theEvent wasKeyEquivalent:(BOOL)equiv;
 - (void)windowDidChangeBackingProperties:(NSNotification*)notification;
 - (void)windowChangedGlobalFrame:(NSNotification*)notification;
@@ -654,8 +652,6 @@ bool RenderWidgetHostViewMac::OnMessageReceived(const IPC::Message& message) {
   IPC_BEGIN_MESSAGE_MAP(RenderWidgetHostViewMac, message)
     IPC_MESSAGE_HANDLER(ViewHostMsg_PluginFocusChanged, OnPluginFocusChanged)
     IPC_MESSAGE_HANDLER(ViewHostMsg_StartPluginIme, OnStartPluginIme)
-    IPC_MESSAGE_HANDLER(ViewHostMsg_DidChangeScrollbarsForMainFrame,
-                        OnDidChangeScrollbarsForMainFrame)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
@@ -1864,12 +1860,6 @@ gfx::GLSurfaceHandle RenderWidgetHostViewMac::GetCompositingSurface() {
   return gfx::GLSurfaceHandle(gfx::kNullPluginWindow, gfx::NATIVE_TRANSPORT);
 }
 
-void RenderWidgetHostViewMac::SetScrollOffsetPinning(
-    bool is_pinned_to_left, bool is_pinned_to_right) {
-  [cocoa_view_ scrollOffsetPinnedToLeft:is_pinned_to_left
-                                toRight:is_pinned_to_right];
-}
-
 bool RenderWidgetHostViewMac::LockMouse() {
   if (mouse_locked_)
     return true;
@@ -2096,11 +2086,6 @@ void RenderWidgetHostViewMac::OnStartPluginIme() {
   [cocoa_view_ setPluginImeActive:YES];
 }
 
-void RenderWidgetHostViewMac::OnDidChangeScrollbarsForMainFrame(
-    bool has_horizontal_scrollbar, bool has_vertical_scrollbar) {
-  [cocoa_view_ setHasHorizontalScrollbar:has_horizontal_scrollbar];
-}
-
 gfx::Rect RenderWidgetHostViewMac::GetScaledOpenGLPixelRect(
     const gfx::Rect& rect) {
   gfx::Rect src_gl_subrect = rect;
@@ -2392,22 +2377,6 @@ void RenderWidgetHostViewMac::AcceleratedLayerDidDrawFrame(bool succeeded) {
   [responderDelegate_ rendererHandledWheelEvent:event consumed:consumed];
 }
 
-- (void)scrollOffsetPinnedToLeft:(BOOL)left toRight:(BOOL)right {
-  if (responderDelegate_ &&
-      [responderDelegate_
-          respondsToSelector:@selector(scrollOffsetPinnedToLeft:toRight:)]) {
-    [responderDelegate_ scrollOffsetPinnedToLeft:left toRight:right];
-  }
-}
-
-- (void)setHasHorizontalScrollbar:(BOOL)has_horizontal_scrollbar {
-  if (responderDelegate_ &&
-      [responderDelegate_
-          respondsToSelector:@selector(setHasHorizontalScrollbar:)]) {
-    [responderDelegate_ setHasHorizontalScrollbar:has_horizontal_scrollbar];
-  }
-}
-
 - (BOOL)respondsToSelector:(SEL)selector {
   // Trickiness: this doesn't mean "does this object's superclass respond to
   // this selector" but rather "does the -respondsToSelector impl from the