exhibit 1: explicit null checks

chrome/browser/ui/browser.cc

 // Copyright (c) 2012 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/ui/browser.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #include <shellapi.h>
 #endif  // OS_WIN
@@ skipping 541 matching lines @@
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 // Browser, State Storage and Retrieval for UI:
 
 SkBitmap Browser::GetCurrentPageIcon() const {
   TabContents* contents = chrome::GetActiveTabContents(this);
   // |contents| can be NULL since GetCurrentPageIcon() is called by the window
   // during the window's creation (before tabs have been added).
   // TODO: Let this return a gfx::Image.
-  return contents ?
-      contents->favicon_tab_helper()->GetFavicon().AsBitmap() : SkBitmap();
+  if (!contents)
+    return SkBitmap();
+  const gfx::Image& icon = contents->favicon_tab_helper()->GetFavicon();
+  return icon.IsEmpty() ? SkBitmap() : *icon.ToSkBitmap();
 }
 
 string16 Browser::GetWindowTitleForCurrentTab() const {
   WebContents* contents = chrome::GetActiveWebContents(this);
   string16 title;
 
   // |contents| can be NULL because GetWindowTitleForCurrentTab is called by the
   // window during the window's creation (before tabs have been added).
   if (contents) {
     title = contents->GetTitle();
@@ skipping 1745 matching lines @@
   if (contents && !allow_js_access) {
     contents->web_contents()->GetController().LoadURL(
         target_url,
         content::Referrer(),
         content::PAGE_TRANSITION_LINK,
         std::string());  // No extra headers.
   }
 
   return contents != NULL;
 }