Remove content dependencies from content settings providers.

chrome/browser/content_settings/content_settings_pref_provider.cc

Index: chrome/browser/content_settings/content_settings_pref_provider.cc
diff --git a/chrome/browser/content_settings/content_settings_pref_provider.cc b/chrome/browser/content_settings/content_settings_pref_provider.cc
index c0a67216ab89c953da273a45d060dae73ae31d43..0cc08576a1f84829a490c169029bbda1b5c079aa 100644
--- a/chrome/browser/content_settings/content_settings_pref_provider.cc
+++ b/chrome/browser/content_settings/content_settings_pref_provider.cc
@@ -9,6 +9,7 @@
 #include <utility>
 
 #include "base/auto_reset.h"
+#include "base/bind.h"
 #include "base/command_line.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram.h"
@@ -25,13 +26,8 @@
 #include "components/content_settings/core/common/content_settings.h"
 #include "components/content_settings/core/common/content_settings_pattern.h"
 #include "components/pref_registry/pref_registry_syncable.h"
-#include "content/public/browser/browser_thread.h"
-#include "content/public/browser/user_metrics.h"
 #include "url/gurl.h"
 
-using base::UserMetricsAction;
-using content::BrowserThread;
-
 namespace {
 
 typedef std::pair<std::string, std::string> StringPair;
@@ -126,7 +122,7 @@ bool PrefProvider::SetWebsiteSetting(
     ContentSettingsType content_type,
     const ResourceIdentifier& resource_identifier,
     base::Value* in_value) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(CalledOnValidThread());

[Bernhard Bauer, 2014/09/23 10:08:19]

Hm... I'm not sure if I actually prefer this. PrefProvider is not just a class
that can only be used on a single thread, it has to be used on the UI thread,
because the PrefService has to be used on the UI thread.

[Jun Mukai, 2014/09/23 20:48:44]

Hmm.  As I wrote in another comment, my motivation is to remove BrowserThread
things if possible.
As far as I see in base/pref_service, PrefService also doesn't care the name of
the thread. It simply belongs to the thread where it was created, so I think it
would be okay to use the same logic here.

If you want to specify the thread name, I think we can use
MessageLoopForUI::IsCurrent() instead of BrowserThread::UI. Which do you prefer?

   DCHECK(prefs_);
   // Default settings are set using a wildcard pattern for both
   // |primary_pattern| and |secondary_pattern|. Don't store default settings in
@@ -180,7 +176,7 @@ bool PrefProvider::SetWebsiteSetting(
 
 void PrefProvider::ClearAllContentSettingsRules(
     ContentSettingsType content_type) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(CalledOnValidThread());
   DCHECK(prefs_);
 
   OriginIdentifierValueMap* map_to_modify = &incognito_value_map_;
@@ -491,7 +487,7 @@ void PrefProvider::ReadContentSettingsFromPref(bool overwrite) {
 }
 
 void PrefProvider::OnContentSettingsPatternPairsChanged() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(CalledOnValidThread());
 
   if (updating_preferences_)
     return;
@@ -561,7 +557,7 @@ void PrefProvider::CanonicalizeContentSettingsExceptions(
 }
 
 void PrefProvider::ShutdownOnUIThread() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(CalledOnValidThread());
   DCHECK(prefs_);
   RemoveAllObservers();
   pref_change_registrar_.RemoveAll();