More CHECKs in my continuing effort to figure out what is going on. Neither ...

chrome/browser/views/autocomplete/autocomplete_popup_contents_view.cc

 // Copyright (c) 2009 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 "chrome/browser/views/autocomplete/autocomplete_popup_contents_view.h"
 
 #include <objidl.h>
 #include <commctrl.h>
 #include <dwmapi.h>
 
@@ skipping 261 matching lines @@
 
 AutocompleteResultView::AutocompleteResultView(
     AutocompleteResultViewModel* model,
     int model_index,
     const gfx::Font& font)
     : model_(model),
       model_index_(model_index),
       hot_(false),
       font_(font),
       mirroring_context_(new MirroringContext()) {
+  CHECK(model_index >= 0);
   InitClass();
 }
 
 AutocompleteResultView::~AutocompleteResultView() {
 }
 
 void AutocompleteResultView::Paint(gfx::Canvas* canvas) {
   canvas->FillRectInt(GetBackgroundColor(), 0, 0, width(), height());
 
   int x = MirroredLeftPointForRect(icon_bounds_);
@@ skipping 578 matching lines @@
   // Allow the window blur effect to show through the popup background.
   SkPaint paint;
   SkColor transparency = GetThemeProvider()->ShouldUseNativeFrame() ?
       kGlassPopupTransparency : kOpaquePopupTransparency;
   paint.setColor(SkColorSetARGB(transparency, 255, 255, 255));
   paint.setPorterDuffXfermode(SkPorterDuff::kDstIn_Mode);
   paint.setStyle(SkPaint::kFill_Style);
   canvas->FillRectInt(0, 0, canvas->getDevice()->width(),
                       canvas->getDevice()->height(), paint);
 }