Re-enable the clang check for enum constants.

tools/clang/plugins/ChromeClassTester.h

Index: tools/clang/plugins/ChromeClassTester.h
diff --git a/tools/clang/plugins/ChromeClassTester.h b/tools/clang/plugins/ChromeClassTester.h
index 588ae9cae5a90fedbcc2c77ec6c19b8ea5609b6e..6bd19a629a8248d9539286653e74e33e393ff7b8 100644
--- a/tools/clang/plugins/ChromeClassTester.h
+++ b/tools/clang/plugins/ChromeClassTester.h
@@ -54,6 +54,12 @@ class ChromeClassTester : public clang::ASTConsumer {
   virtual void CheckChromeClass(clang::SourceLocation record_location,
                                 clang::CXXRecordDecl* record) = 0;
 
+  // Filtered versions of enum type that are only called with things defined
+  // in chrome header files.
+  virtual void CheckChromeEnum(clang::SourceLocation enum_location,
+                               clang::EnumDecl* enum_decl) {
+  }
+
   // Utility methods used for filtering out non-chrome classes (and ones we
   // deliberately ignore) in HandleTagDeclDefinition().
   std::string GetNamespaceImpl(const clang::DeclContext* context,