Factor out core logic from OnCanAccessFile() and add tests for it

chrome/browser/net/chrome_network_delegate.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_NET_CHROME_NETWORK_DELEGATE_H_
 #define CHROME_BROWSER_NET_CHROME_NETWORK_DELEGATE_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 59 matching lines @@
   void set_url_blacklist_manager(
       const policy::URLBlacklistManager* url_blacklist_manager) {
     url_blacklist_manager_ = url_blacklist_manager;
   }
 
   // If |profile| is nullptr or not set, events will be broadcast to all
   // profiles, otherwise they will only be sent to the specified profile.
   // Also pass through to ChromeExtensionsNetworkDelegate::set_profile().
   void set_profile(void* profile);
 
-  // |profile_path| is used to locate the "Downloads" folder on Chrome OS. If it
-  // is set, the location of the Downloads folder for the profile is added to
-  // the whitelist for accesses via file: scheme.
+  // |profile_path| is used to locate profile specific paths such as the
+  // "Downloads" folder on Chrome OS. If it is set, folders like Downloads
+  // for the profile are added to the whitelist for accesses via file: scheme.
   void set_profile_path(const base::FilePath& profile_path) {
     profile_path_ = profile_path;
   }
 
   // If |cookie_settings| is nullptr or not set, all cookies are enabled,
   // otherwise the settings are enforced on all observed network requests.
   // Not inlined because we assign a scoped_refptr, which requires us to include
   // the header file. Here we just forward-declare it.
   void set_cookie_settings(content_settings::CookieSettings* cookie_settings);
 
@@ skipping 29 matching lines @@
   // |enable_referrers| cannot be nullptr, the others can.
   // This method should be called on the UI thread.
   static void InitializePrefsOnUIThread(
       BooleanPrefMember* enable_referrers,
       BooleanPrefMember* enable_do_not_track,
       BooleanPrefMember* force_google_safe_search,
       IntegerPrefMember* force_youtube_restrict,
       StringPrefMember* allowed_domains_for_apps,
       PrefService* pref_service);
 
+  // Returns true if access to |path| is allowed. |profile_path| is used to
+  // locate certain paths on Chrome OS. See set_profile_path() for details.
+  static bool IsAccessAllowed(const base::FilePath& path,
+                              const base::FilePath& profile_path);
+
  private:
   // NetworkDelegate implementation.
   int OnBeforeURLRequest(net::URLRequest* request,
                          const net::CompletionCallback& callback,
                          GURL* new_url) override;
   int OnBeforeStartTransaction(net::URLRequest* request,
                                const net::CompletionCallback& callback,
                                net::HttpRequestHeaders* headers) override;
   void OnStartTransaction(net::URLRequest* request,
                           const net::HttpRequestHeaders& headers) override;
@@ skipping 65 matching lines @@
 
   // Aggregates and reports network usage.
   data_usage::DataUseAggregator* data_use_aggregator_;
   // Controls whether network usage is reported as being off the record.
   bool is_data_usage_off_the_record_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeNetworkDelegate);
 };
 
 #endif  // CHROME_BROWSER_NET_CHROME_NETWORK_DELEGATE_H_