Fix a typo in gpu_info_collector_linux.cc.

content/gpu/gpu_info_collector_linux.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 "content/gpu/gpu_info_collector.h"
 
 #include <dlfcn.h>
 #include <X11/Xlib.h>
 #include <vector>
 
@@ skipping 161 matching lines @@
 // Use NVCtrl extention to query NV driver version.
 // Return empty string on failing.
 std::string CollectDriverVersionNVidia() {
   Display* display = base::MessagePumpForUI::GetDefaultXDisplay();
   if (!display) {
     LOG(ERROR) << "XOpenDisplay failed.";
     return std::string();
   }
   int event_base = 0, error_base = 0;
   if (!XNVCTRLQueryExtension(display, &event_base, &error_base)) {
-    LOG(INFO) << "NVCtrl extension does not exits.";
+    LOG(INFO) << "NVCtrl extension does not exist.";
     return std::string();
   }
   int screen_count = ScreenCount(display);
   for (int screen = 0; screen < screen_count; ++screen) {
     char* buffer = NULL;
     if (XNVCTRLIsNvScreen(display, screen) &&
         XNVCTRLQueryStringAttribute(display, screen, 0,
                                     NV_CTRL_STRING_NVIDIA_DRIVER_VERSION,
                                     &buffer)) {
       std::string driver_version(buffer);
@@ skipping 182 matching lines @@
     return false;
   if (pos != std::string::npos)
     driver_version = driver_version.substr(0, pos);
 
   gpu_info->driver_vendor = pieces[1];
   gpu_info->driver_version = driver_version;
   return true;
 }
 
 }  // namespace gpu_info_collector