[Mac] Puts a NULL check in case a native plugin library cannot be loaded (.dl...

webkit/glue/plugins/plugin_lib_mac.mm

 // Copyright (c) 2006-2009 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.
 
 #import <Carbon/Carbon.h>
 
 #include "webkit/glue/plugins/plugin_lib.h"
 
 #include "base/native_library.h"
 #include "base/scoped_cftyperef.h"
@@ skipping 293 matching lines @@
   // (1) <<plugindescription>>
   // (2) <<pluginname>>
   //
   // Strictly speaking, only STR# 128 is required.
 
   // We are accessing the bundle contained in the NativeLibrary but not
   // unloading it.  We use a scoped_ptr to make sure the NativeLibraryStruct is
   // not leaked.
   scoped_ptr<base::NativeLibraryStruct> native_library(
       base::LoadNativeLibrary(filename));
-  if (native_library->type != base::BUNDLE)
+  if (!native_library.get() || native_library->type != base::BUNDLE)
     return false;
   scoped_cftyperef<CFBundleRef> bundle(native_library->bundle);
   if (!bundle)
     return false;
 
   // preflight
 
   OSType type = 0;
   CFBundleGetPackageInfo(bundle.get(), &type, NULL);
   if (type != FOUR_CHAR_CODE('BRPL'))
@@ skipping 11 matching lines @@
 
   if (ReadSTRPluginInfo(filename, bundle.get(), info))
     return true;
 
   // ... or not
 
   return false;
 }
 
 }  // namespace NPAPI