Fix "unreachable code" warnings (MSVC warning 4702) in chrome/browser/.

chrome/browser/ui/search/search_tab_helper.cc

 // Copyright 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/search/search_tab_helper.h"
 
 #include <set>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram.h"
@@ skipping 124 matching lines @@
     return;
 
   base::TimeDelta duration =
       base::TimeTicks::Now() - core_tab_helper->new_tab_start_time();
   UMA_HISTOGRAM_TIMES("Tab.NewTabOnload", duration);
   core_tab_helper->set_new_tab_start_time(base::TimeTicks());
 }
 
 // Returns the OmniboxView for |contents| or NULL if not available.
 OmniboxView* GetOmniboxView(content::WebContents* contents) {
-  if (!contents)
+  // iOS and Android don't use the Instant framework.
+#if defined(OS_IOS) || defined(OS_ANDROID)
+  return NULL;
+#else
+  if (contents)
     return NULL;
-
-  // iOS and Android don't use the Instant framework.
-#if !defined(OS_IOS) && !defined(OS_ANDROID)
   Browser* browser = chrome::FindBrowserWithWebContents(contents);
   return browser ? browser->window()->GetLocationBar()->GetOmniboxView() : NULL;
 #endif
-  return NULL;
 }
 
 }  // namespace
 
 SearchTabHelper::SearchTabHelper(content::WebContents* web_contents)
     : WebContentsObserver(web_contents),
       is_search_enabled_(chrome::IsInstantExtendedAPIEnabled()),
       web_contents_(web_contents),
       ipc_router_(web_contents, this,
                   make_scoped_ptr(new SearchIPCRouterPolicyImpl(web_contents))
@@ skipping 466 matching lines @@
   // Don't push a history entry.
   load_params.should_replace_current_entry = true;
   web_contents_->GetController().LoadURLWithParams(load_params);
 }
 
 bool SearchTabHelper::IsInputInProgress() const {
   OmniboxView* omnibox = GetOmniboxView(web_contents());
   return !model_.mode().is_ntp() && omnibox &&
       omnibox->model()->focus_state() == OMNIBOX_FOCUS_VISIBLE;
 }