[subresource_filter] Use constexpr for subresource filter dev tools messages.

components/subresource_filter/core/browser/subresource_filter_constants.cc

Index: components/subresource_filter/core/browser/subresource_filter_constants.cc
diff --git a/components/subresource_filter/core/browser/subresource_filter_constants.cc b/components/subresource_filter/core/browser/subresource_filter_constants.cc
index fc3aaba8ab932f831f12a5425e2bc358888d3ced..dbc9e0999c042c38fdf1126649024035fbd2860e 100644
--- a/components/subresource_filter/core/browser/subresource_filter_constants.cc
+++ b/components/subresource_filter/core/browser/subresource_filter_constants.cc
@@ -30,11 +30,4 @@ const base::FilePath::CharType kUnindexedRulesetLicenseFileName[] =
 const base::FilePath::CharType kUnindexedRulesetDataFileName[] =
     FILE_PATH_LITERAL("Filtering Rules");
 
-// TODO(shivanisha): Update the strings when finalized.
-
-const std::string kActivationConsoleMessage =
-    "Subresource filter is activated on this site";
-
-const std::string kDisallowSubframeConsoleMessage =
-    "Subresource filtering disallowed loading this resource, ";
 }  // namespace subresource_filter