Remove RuntimeAPIDelegate::GetPreviousVersion.

extensions/browser/extension_registry.cc

Index: extensions/browser/extension_registry.cc
diff --git a/extensions/browser/extension_registry.cc b/extensions/browser/extension_registry.cc
index 9c2bf16f53ec80f74192f883ae8753bbd51d8638..24ef83b54c86e432ffc7d15096cdf45ea177e5a8 100644
--- a/extensions/browser/extension_registry.cc
+++ b/extensions/browser/extension_registry.cc
@@ -40,6 +40,15 @@ std::unique_ptr<ExtensionSet> ExtensionRegistry::GenerateInstalledExtensionsSet(
   return installed_extensions;
 }
 
+base::Version ExtensionRegistry::GetStoredVersion(const ExtensionId& id) const {
+  // TODO(lazyboy): Why not TERMINATED? https://crbug.com/724563.
+  int include_mask = ExtensionRegistry::ENABLED | ExtensionRegistry::DISABLED |
+                     ExtensionRegistry::BLACKLISTED |
+                     ExtensionRegistry::BLOCKED;
+  const Extension* registry_extension = GetExtensionById(id, include_mask);
+  return registry_extension ? *registry_extension->version() : base::Version();
+}
+
 void ExtensionRegistry::AddObserver(ExtensionRegistryObserver* observer) {
   observers_.AddObserver(observer);
 }