Convert //components/web_resource away from base::Bind()

As part of the effort to replace base::Bind by
base::Bind{Once, Repeating}, this CL converts the one usage of
base::Bind() in //components/web_resource to instead be a usage of
base::BindRepeating(). The rational for using base::BindRepeating() is
that the callback is being passed in to a PrefChangeRegistrar, which
can invoke it multiple times in response to pref changes.

This CL also takes the opportunity to update the PrefChangeRegistrar
API in question to take in a base::RepeatingClosure rather than a
base::Closure.

TBR=jochen@chromium.org

Bug: 1007753
Change-Id: I7550f64eedb9d0da719f9ff8617e2c4d9d415eab
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1847216
Commit-Queue: Colin Blundell <blundell@chromium.org>
Reviewed-by: danakj <danakj@chromium.org>
Cr-Commit-Position: refs/heads/master@{#705009}

PRESUBMIT.py

@@ -380,7 +380,6 @@ _NOT_CONVERTED_TO_MODERN_BIND_AND_CALLBACK = '|'.join((
   '^components/variations/',
   '^components/visitedlink/',
   '^components/web_cache/',
-  '^components/web_resource/',
   '^components/webcrypto/',
   '^components/webdata/',
   '^components/webdata_services/',

components/prefs/pref_change_registrar.cc

@@ -24,8 +24,9 @@ void PrefChangeRegistrar::Init(PrefService* service) {
 }
 
 void PrefChangeRegistrar::Add(const std::string& path,
-                              const base::Closure& obs) {
-  Add(path, base::Bind(&PrefChangeRegistrar::InvokeUnnamedCallback, obs));
+                              const base::RepeatingClosure& obs) {
+  Add(path,
+      base::BindRepeating(&PrefChangeRegistrar::InvokeUnnamedCallback, obs));
 }
 
 void PrefChangeRegistrar::Add(const std::string& path,
@@ -81,9 +82,9 @@ void PrefChangeRegistrar::OnPreferenceChanged(PrefService* service,
     observers_[pref].Run(pref);
 }
 
-void PrefChangeRegistrar::InvokeUnnamedCallback(const base::Closure& callback,
+void PrefChangeRegistrar::InvokeUnnamedCallback(base::OnceClosure callback,
                                                 const std::string& pref_name) {
-  callback.Run();
+  std::move(callback).Run();
 }
 
 PrefService* PrefChangeRegistrar::prefs() {

components/prefs/pref_change_registrar.h

@@ -40,7 +40,7 @@ class COMPONENTS_PREFS_EXPORT PrefChangeRegistrar final : public PrefObserver {
   // the preference that is changing as its parameter.
   //
   // Only one observer may be registered per path.
-  void Add(const std::string& path, const base::Closure& obs);
+  void Add(const std::string& path, const base::RepeatingClosure& obs);
   void Add(const std::string& path, const NamedChangeCallback& obs);
 
   // Removes the pref observer registered for |path|.
@@ -67,7 +67,7 @@ class COMPONENTS_PREFS_EXPORT PrefChangeRegistrar final : public PrefObserver {
   void OnPreferenceChanged(PrefService* service,
                            const std::string& pref_name) override;
 
-  static void InvokeUnnamedCallback(const base::Closure& callback,
+  static void InvokeUnnamedCallback(base::OnceClosure callback,
                                     const std::string& pref_name);
 
   using ObserverMap = std::map<std::string, NamedChangeCallback>;

components/web_resource/eula_accepted_notifier.cc

@@ -33,7 +33,7 @@ bool EulaAcceptedNotifier::IsEulaAccepted() {
   if (registrar_.IsEmpty()) {
     registrar_.Init(local_state_);
     registrar_.Add(prefs::kEulaAccepted,
-                   base::Bind(&EulaAcceptedNotifier::OnPrefChanged,
+                   base::BindRepeating(&EulaAcceptedNotifier::OnPrefChanged,
                                        base::Unretained(this)));
   }
   return false;