Revert 36541 (which went in without any commit log by some black magic). ...

chrome/browser/extensions/extension_tabs_module.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/extensions/extension_tabs_module.h"
 
 #include "app/gfx/codec/jpeg_codec.h"
 #include "base/base64.h"
 #include "base/string_util.h"
 #include "chrome/browser/browser.h"
@@ skipping 814 matching lines @@
       reinterpret_cast<const char*>(&jpeg_data->data[0]),
       jpeg_data->data.size());
 
   base::Base64Encode(stream_as_string, &base64_result);
   base64_result.insert(0, "data:image/jpg;base64,");
   result_.reset(new StringValue(base64_result));
   SendResponse(true);
 }
 
 bool DetectTabLanguageFunction::RunImpl() {
+  #if !defined(OS_WIN)
+    error_ = keys::kSupportedInWindowsOnlyError;
+    return false;
+  #endif
+
   int tab_id = 0;
   Browser* browser = NULL;
   TabContents* contents = NULL;
 
   // If |tab_id| is specified, look for it. Otherwise default to selected tab
   // in the current window.
   if (!args_->IsType(Value::TYPE_NULL)) {
     EXTENSION_FUNCTION_VALIDATE(args_->GetAsInteger(&tab_id));
     if (!GetTabById(tab_id, profile(), &browser, NULL, &contents, NULL,
         &error_)) {
@@ skipping 59 matching lines @@
   if (ExtensionTabUtil::GetTabById(tab_id, profile, browser, tab_strip,
                                    contents, tab_index))
     return true;
 
   if (error_message)
     *error_message = ExtensionErrorUtils::FormatErrorMessage(
         keys::kTabNotFoundError, IntToString(tab_id));
 
   return false;
 }