Make string_util::WriteInto() DCHECK() that the supplied |length_with_null| > 1, meaning that the...

chrome/browser/browser_focus_uitest.cc

 // Copyright (c) 2011 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 "build/build_config.h"
 
 #include "base/file_util.h"
 #include "base/format_macros.h"
 #include "base/message_loop.h"
 #include "base/path_service.h"
@@ skipping 72 matching lines @@
 const char kTypicalPageName[] = "typical_page.html";
 
 // Test to make sure Chrome is in the foreground as we start testing. This is
 // required for tests that synthesize input to the Chrome window.
 bool ChromeInForeground() {
 #if defined(OS_WIN)
   HWND window = ::GetForegroundWindow();
   std::wstring caption;
   std::wstring filename;
   int len = ::GetWindowTextLength(window) + 1;
-  ::GetWindowText(window, WriteInto(&caption, len), len);
+  if (len > 1)
+    ::GetWindowText(window, WriteInto(&caption, len), len);
   bool chrome_window_in_foreground =
       EndsWith(caption, L" - Google Chrome", true) ||
       EndsWith(caption, L" - Chromium", true);
   if (!chrome_window_in_foreground) {
     DWORD process_id;
     int thread_id = ::GetWindowThreadProcessId(window, &process_id);
 
     base::ProcessHandle process;
     if (base::OpenProcessHandleWithAccess(process_id,
                                           PROCESS_QUERY_LIMITED_INFORMATION,
                                           &process)) {
-      len = MAX_PATH;
-      if (!GetProcessImageFileName(process, WriteInto(&filename, len), len)) {
+      if (!GetProcessImageFileName(process, WriteInto(&filename, MAX_PATH),
+                                   MAX_PATH)) {
         int error = GetLastError();
         filename = std::wstring(L"Unable to read filename for process id '" +
                                 base::IntToString16(process_id) +
                                 L"' (error ") +
                                 base::IntToString16(error) + L")";
       }
       base::CloseProcessHandle(process);
     }
   }
   EXPECT_TRUE(chrome_window_in_foreground)
@@ skipping 787 matching lines @@
     browser()->Reload(CURRENT_TAB);
     observer.Wait();
   }
 
   // Focus should now be on the tab contents.
   browser()->ShowDownloadsTab();
   ASSERT_TRUE(IsViewFocused(VIEW_ID_TAB_CONTAINER_FOCUS_VIEW));
 }
 
 }  // namespace