Add migration code to change existing domain scoped content settings to be origin scoped

components/content_settings/core/common/content_settings_pattern.cc

 // 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.
 
 #include "components/content_settings/core/common/content_settings_pattern.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <vector>
@@ skipping 421 matching lines @@
 ContentSettingsPattern ContentSettingsPattern::FromString(
     const std::string& pattern_spec) {
   std::unique_ptr<ContentSettingsPattern::BuilderInterface> builder(
       ContentSettingsPattern::CreateBuilder(false));
   content_settings::PatternParser::Parse(pattern_spec,
                                          builder.get());
   return builder->Build();
 }
 
 // static
+bool ContentSettingsPattern::MigrateFromDomainToOrigin(
+    const ContentSettingsPattern& domain_pattern,
+    ContentSettingsPattern* origin_pattern) {
+  DCHECK(origin_pattern);
+
+  // Generated patterns with ::FromURL (which we want to migrate) must either
+  // have a scheme wildcard or be https.
+  if (domain_pattern.parts_.scheme != url::kHttpsScheme &&
+      !domain_pattern.parts_.is_scheme_wildcard) {
+    return false;
+  }
+
+  // Generated patterns using ::FromURL with the HTTPs scheme can not have a
+  // port wildcard.
+  if (domain_pattern.parts_.is_port_wildcard &&
+      domain_pattern.parts_.scheme == url::kHttpsScheme) {
+    return false;
+  }
+
+  // Patterns generated with ::FromURL will always have a domain wildcard. Those
+  // generated with ::FromURLNoWildcard don't.
+  if (!domain_pattern.parts_.has_domain_wildcard)
+    return false;
+
+  // Generated patterns with ::FromURL will always have a host.
+  if (domain_pattern.parts_.host.empty())
+    return false;
+
+  std::unique_ptr<ContentSettingsPattern::BuilderInterface> builder(
+      ContentSettingsPattern::CreateBuilder(false));
+
+  if (domain_pattern.parts_.is_scheme_wildcard)
+    builder->WithScheme(url::kHttpScheme);
+  else
+    builder->WithScheme(domain_pattern.parts_.scheme);
+
+  builder->WithHost(domain_pattern.parts_.host);
+
+  if (domain_pattern.parts_.is_port_wildcard) {

[msramek, 2016/07/07 12:19:24]

This logic is exactly what the PatternParser does
(https://cs.chromium.org/chromium/src/components/content_settings/core/common/...).

I wonder if it can therefore be simplified, but probably not without outputting
it to a string and then using the parser.

[lshang, 2016/07/08 01:19:43]

Since we need to generate a new pattern which is based on the old pattern but
have different pattern component values, I think this is clearer than using
parsers to show how each component is set.

+    if (domain_pattern.parts_.scheme == url::kHttpsScheme) {
+      builder->WithPort(GetDefaultPort(url::kHttpsScheme));
+    } else {
+      builder->WithPort(GetDefaultPort(url::kHttpScheme));
+    }
+  } else {
+    builder->WithPort(domain_pattern.parts_.port);
+  }
+
+  *origin_pattern = builder->Build();
+
+  return true;
+}
+
+// static
 void ContentSettingsPattern::SetNonWildcardDomainNonPortScheme(
     const char* scheme) {
   DCHECK(scheme);
   DCHECK(!non_port_non_domain_wildcard_scheme ||
          non_port_non_domain_wildcard_scheme == scheme);
   non_port_non_domain_wildcard_scheme = scheme;
 }
 
 // static
 bool ContentSettingsPattern::IsNonWildcardDomainNonPortScheme(
@@ skipping 285 matching lines @@
   if (!parts.is_path_wildcard && other_parts.is_path_wildcard)
     return ContentSettingsPattern::PREDECESSOR;
 
   int result = parts.path.compare(other_parts.path);
   if (result == 0)
     return ContentSettingsPattern::IDENTITY;
   if (result > 0)
     return ContentSettingsPattern::DISJOINT_ORDER_PRE;
   return ContentSettingsPattern::DISJOINT_ORDER_POST;
 }