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

chrome/browser/content_settings/host_content_settings_map_unittest.cc

Index: chrome/browser/content_settings/host_content_settings_map_unittest.cc
diff --git a/chrome/browser/content_settings/host_content_settings_map_unittest.cc b/chrome/browser/content_settings/host_content_settings_map_unittest.cc
index b890f952115b1943981eac74753a6f702f02d848..1e415f40f21f261d5eb1a6acd74cfc5ac6c718f0 100644
--- a/chrome/browser/content_settings/host_content_settings_map_unittest.cc
+++ b/chrome/browser/content_settings/host_content_settings_map_unittest.cc
@@ -232,7 +232,7 @@ TEST_F(HostContentSettingsMapTest, Clear) {
 #endif
 }
 
-TEST_F(HostContentSettingsMapTest, Patterns) {
+TEST_F(HostContentSettingsMapTest, Origins) {

[msramek, 2016/04/19 18:51:34]

Hmm. This test indeed doesn't test patterns anymore, but it should.

It seems that in https://codereview.chromium.org/1686343002 we removed patterns
from this test (because the HostContentSettingsMap interface stopped supporting
them), but in fact we should have just used another way of setting them (like
writing directly into the preference file), so that this test still could test
patterns. We lost that test coverage.

The same is true of NestedSettings below. Origins and NestedSettings tests are
almost equivalent right now.

(this is unrelated to this CL, I just spotted it because of this change; I can
look into that myself later)

[raymes, 2016/04/20 01:53:21]

That's a good point. We can still test patterns here by setting a custom-scoped
setting and that seems like a good idea to keep test coverage.

[lshang, 2016/06/15 06:26:41]

Yep, I've changed it back to explicitly use patterns to keep test coverage.

[lshang, 2016/06/15 06:26:41]

As above.

   TestingProfile profile;
   HostContentSettingsMap* host_content_settings_map =
       HostContentSettingsMapFactory::GetForProfile(&profile);
@@ -249,7 +249,7 @@ TEST_F(HostContentSettingsMapTest, Patterns) {
   EXPECT_EQ(CONTENT_SETTING_BLOCK,
             host_content_settings_map->GetContentSetting(
                 host1, host1, CONTENT_SETTINGS_TYPE_IMAGES, std::string()));
-  EXPECT_EQ(CONTENT_SETTING_BLOCK,
+  EXPECT_EQ(CONTENT_SETTING_ALLOW,
             host_content_settings_map->GetContentSetting(
                 host2, host2, CONTENT_SETTINGS_TYPE_IMAGES, std::string()));
   EXPECT_EQ(CONTENT_SETTING_ALLOW,
@@ -271,7 +271,7 @@ TEST_F(HostContentSettingsMapTest, Observer) {
 
   GURL host("http://example.com/");
   ContentSettingsPattern primary_pattern =
-      ContentSettingsPattern::FromString("[*.]example.com");
+      ContentSettingsPattern::FromString("http://example.com:80");
   ContentSettingsPattern secondary_pattern =
       ContentSettingsPattern::Wildcard();
   EXPECT_CALL(observer,
@@ -544,12 +544,14 @@ TEST_F(HostContentSettingsMapTest, NestedSettings) {
   host_content_settings_map->SetDefaultContentSetting(
       CONTENT_SETTINGS_TYPE_JAVASCRIPT, CONTENT_SETTING_BLOCK);
 
-  EXPECT_EQ(CONTENT_SETTING_BLOCK,
+  // Cookies and Images only take effect per-origin.

[raymes, 2016/04/20 01:53:21]

Same here, I think since this test explicitly tests patterns, we should keep
that test coverage by manually setting up the patterns.

[lshang, 2016/06/15 06:26:41]

Done.

+  EXPECT_EQ(CONTENT_SETTING_ALLOW,
             host_content_settings_map->GetContentSetting(
                 host, host, CONTENT_SETTINGS_TYPE_COOKIES, std::string()));
-  EXPECT_EQ(CONTENT_SETTING_BLOCK,
+  EXPECT_EQ(CONTENT_SETTING_ALLOW,
             host_content_settings_map->GetContentSetting(
                 host, host, CONTENT_SETTINGS_TYPE_IMAGES, std::string()));
+  // Default settings affect all sites which have no exceptions.
   EXPECT_EQ(CONTENT_SETTING_BLOCK,
             host_content_settings_map->GetContentSetting(
                 host, host, CONTENT_SETTINGS_TYPE_JAVASCRIPT, std::string()));
@@ -1053,7 +1055,7 @@ TEST_F(HostContentSettingsMapTest, AddContentSettingsObserver) {
 
   GURL host("http://example.com/");
   ContentSettingsPattern pattern =
-      ContentSettingsPattern::FromString("[*.]example.com");
+      ContentSettingsPattern::FromString("http://example.com:80");
   EXPECT_CALL(mock_observer,
               OnContentSettingChanged(pattern,
                                       ContentSettingsPattern::Wildcard(),