Allow startup with missing V8 snapshot file.

chrome/browser/chrome_content_browser_client.h

 // 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.
 
 #ifndef CHROME_BROWSER_CHROME_CONTENT_BROWSER_CLIENT_H_
 #define CHROME_BROWSER_CHROME_CONTENT_BROWSER_CLIENT_H_
 
 #include <set>
 #include <string>
 #include <utility>
@@ skipping 94 matching lines @@
       const GURL& new_url) override;
   bool ShouldSwapProcessesForRedirect(
       content::ResourceContext* resource_context,
       const GURL& current_url,
       const GURL& new_url) override;
   bool ShouldAssignSiteForURL(const GURL& url) override;
   std::string GetCanonicalEncodingNameByAliasName(
       const std::string& alias_name) override;
   void AppendExtraCommandLineSwitches(base::CommandLine* command_line,
                                       int child_process_id) override;
+  void AppendMappedFileCommandLineSwitches(
+      base::CommandLine* command_line) override;
   std::string GetApplicationLocale() override;
   std::string GetAcceptLangs(content::BrowserContext* context) override;
   const gfx::ImageSkia* GetDefaultFavicon() override;
   bool AllowAppCache(const GURL& manifest_url,
                      const GURL& first_party,
                      content::ResourceContext* context) override;
   bool AllowServiceWorker(const GURL& scope,
                           const GURL& first_party,
                           content::ResourceContext* context,
                           int render_process_id,
@@ skipping 172 matching lines @@
   // Set of origins that can get a handle for FileIO from NaCl.
   std::set<std::string> allowed_file_handle_origins_;
   // Set of origins that can use "dev chanel" APIs from NaCl, even on stable
   // versions of Chrome.
   std::set<std::string> allowed_dev_channel_origins_;
 #endif
 
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
   base::ScopedFD v8_natives_fd_;
   base::ScopedFD v8_snapshot_fd_;
+  bool natives_fd_exists() { return v8_natives_fd_ != -1; }
+  bool snapshot_fd_exists() { return v8_snapshot_fd_ != -1; }
 #endif  // OS_POSIX && !OS_MACOSX
 
   // Vector of additional ChromeContentBrowserClientParts.
   // Parts are deleted in the reverse order they are added.
   std::vector<ChromeContentBrowserClientParts*> extra_parts_;
 
   base::WeakPtrFactory<ChromeContentBrowserClient> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeContentBrowserClient);
 };
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_CHROME_CONTENT_BROWSER_CLIENT_H_