Add removal filter support for Cookies, Storage, and Content Settings.

components/content_settings/core/browser/host_content_settings_map.h

Index: components/content_settings/core/browser/host_content_settings_map.h
diff --git a/components/content_settings/core/browser/host_content_settings_map.h b/components/content_settings/core/browser/host_content_settings_map.h
index 98fe724f79dc75b7aa9aebc0b87c4d8e0ebe80cc..cd695516c6e90c16c238f086200ac008ec37a049 100644
--- a/components/content_settings/core/browser/host_content_settings_map.h
+++ b/components/content_settings/core/browser/host_content_settings_map.h
@@ -12,6 +12,7 @@
 #include <string>
 #include <vector>
 
+#include "base/callback_forward.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/observer_list.h"
@@ -188,6 +189,18 @@ class HostContentSettingsMap : public content_settings::Observer,
   // This should only be called on the UI thread.
   void ClearSettingsForOneType(ContentSettingsType content_type);
 
+
+  // Clears all host-specific settings for one content type that satisfy the
+  // given predicate.
+  //
+  // This should only be called on the UI thread.
+  void ClearSettingsForOneTypeWithPredicate(

[raymes, 2016/02/29 00:44:59]

Hey Daniel, we chatted about potentially using GetSettingsForOneType to get the
settings  and then iterate through them and delete them. Would that be possible?

I'd rather not add new APIs here if we can avoid it - the interface is already a
bit of a mess.

Thanks!

[msramek, 2016/02/29 17:46:07]

I would disagree. If the deletion is done in an iterative manner, and the only
distinction is whether or not a filter is applied, then we can use the same
method. However, ClearContentSettingsForOneType is implemented by nuking the
preference, so this would decrease performance.

Arguably, it's not super-important for content settings, since the amount of
data stored tends to be low, but ClearAll() and ClearWithSomeConstraints(...) is
going to be a pattern that will appear all over Chrome as we keep plumbing
origin-based deletion to other backends.

[dmurph, 2016/03/01 00:10:00]

I moved the method to a static method in the BrowsingDataRemover (and moved
test), as it doesn't really need any private data. Let me know what you guys
prefer. It can be moved back.

[raymes, 2016/03/01 00:14:50]

Great, thanks! This sounds much better :)

+      ContentSettingsType content_type,
+      const base::Callback<
+          bool(const ContentSettingsPattern& primary_pattern,
+               const ContentSettingsPattern& secondary_pattern)>
+          predicate);
+
   static bool IsDefaultSettingAllowedForType(ContentSetting setting,
                                              ContentSettingsType content_type);