Check pref before running DNS probes

Right now, the NetErrorTabHelper assumes it's never allowed to run probes.
This change checks the "Use web service to resolve navigation errors" pref
and allows probes to run if it's checked.

BUG=156415


Review URL: https://chromiumcodereview.appspot.com/11418074

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@169109 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 13 insertions, 4 deletions

diff --git a/chrome/browser/net/net_error_tab_helper.h b/chrome/browser/net/net_error_tab_helper.h
index 4793bab..2a4c905 100644
--- a/chrome/browser/net/net_error_tab_helper.h
+++ b/chrome/browser/net/net_error_tab_helper.h
@@ -8,6 +8,7 @@
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/weak_ptr.h"
+#include "chrome/browser/api/prefs/pref_member.h"
 #include "chrome/browser/net/dns_probe_service.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
@@ -34,6 +35,8 @@ class NetErrorTabHelper
 
   void OnDnsProbeFinished(DnsProbeService::Result result);
 
+  static void set_enabled_for_testing(bool enabled_for_testing);
+
  protected:
   friend class content::WebContentsUserData<NetErrorTabHelper>;
 
@@ -44,20 +47,26 @@ class NetErrorTabHelper
   // Posts a task to the IO thread that will start a DNS probe.
   virtual void PostStartDnsProbeTask();
 
-  // Checks if the "Use web service to resolve navigation errors" preference is
-  // enabled on the profile.
-  virtual bool DnsProbesAllowedByPref() const;
+  // Checks if probes are allowed by enabled_for_testing and "use web service"
+  // pref.
+  virtual bool ProbesAllowed() const;
 
   bool dns_probe_running() { return dns_probe_running_; }
   void set_dns_probe_running(bool running) { dns_probe_running_ = running; }
 
  private:
+  void InitializePref(content::WebContents* contents);
+
   void OnMainFrameDnsError();
 
   // Whether the tab helper has started a DNS probe that has not yet returned
   // a result.
   bool dns_probe_running_;
-
+  // "Use a web service to resolve navigation errors" preference is required
+  // to allow probes.
+  BooleanPrefMember resolve_errors_with_web_service_;
+  // Whether the above pref was initialized -- will be false in unit tests.
+  bool pref_initialized_;
   base::WeakPtrFactory<NetErrorTabHelper> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(NetErrorTabHelper);