It turns out I had the sense of the GetLocalBounds bool wrong everywhere, so ...

views/controls/scroll_view.cc

 // Copyright (c) 2010 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 "views/controls/scroll_view.h"
 
 #include "base/logging.h"
 #include "views/controls/scrollbar/native_scroll_bar.h"
 #include "views/widget/root_view.h"
 
@@ skipping 129 matching lines @@
 
 void ScrollView::Layout() {
   // Most views will want to auto-fit the available space. Most of them want to
   // use the all available width (without overflowing) and only overflow in
   // height. Examples are HistoryView, MostVisitedView, DownloadTabView, etc.
   // Other views want to fit in both ways. An example is PrintView. To make both
   // happy, assume a vertical scrollbar but no horizontal scrollbar. To
   // override this default behavior, the inner view has to calculate the
   // available space, used ComputeScrollBarsVisibility() to use the same
   // calculation that is done here and sets its bound to fit within.
-  gfx::Rect viewport_bounds = GetContentsBounds();
+  gfx::Rect viewport_bounds = GetLocalBounds();
   // Realign it to 0 so it can be used as-is for SetBounds().
   viewport_bounds.set_origin(gfx::Point(0, 0));
   // viewport_size is the total client space available.
   gfx::Size viewport_size = viewport_bounds.size();
   if (viewport_bounds.IsEmpty()) {
     // There's nothing to layout.
     return;
   }
 
   // Assumes a vertical scrollbar since most the current views are designed for
@@ skipping 340 matching lines @@
 
 VariableRowHeightScrollHelper::RowInfo
     FixedRowHeightScrollHelper::GetRowInfo(int y) {
   if (y < top_margin_)
     return RowInfo(0, top_margin_);
   return RowInfo((y - top_margin_) / row_height_ * row_height_ + top_margin_,
                  row_height_);
 }
 
 }  // namespace views