Add type for testing to interstitials.

components/data_reduction_proxy/content/browser/data_reduction_proxy_debug_blocking_page.cc

Index: components/data_reduction_proxy/content/browser/data_reduction_proxy_debug_blocking_page.cc
diff --git a/components/data_reduction_proxy/content/browser/data_reduction_proxy_debug_blocking_page.cc b/components/data_reduction_proxy/content/browser/data_reduction_proxy_debug_blocking_page.cc
index a069781d11d578fc269794913413080bdbf9fc28..54b5893af1beb9aaccb1af3485960c1436177023 100644
--- a/components/data_reduction_proxy/content/browser/data_reduction_proxy_debug_blocking_page.cc
+++ b/components/data_reduction_proxy/content/browser/data_reduction_proxy_debug_blocking_page.cc
@@ -64,6 +64,11 @@ static base::LazyInstance<DataReductionProxyDebugBlockingPageFactoryImpl>
     g_data_reduction_proxy_blocking_page_factory_impl =
         LAZY_INSTANCE_INITIALIZER;
 
+// static
+content::InterstitialPageDelegate::TypeID
+    DataReductionProxyDebugBlockingPage::kTypeForTesting =
+        &DataReductionProxyDebugBlockingPage::kTypeForTesting;
+
 DataReductionProxyDebugBlockingPage::DataReductionProxyDebugBlockingPage(
     DataReductionProxyDebugUIManager* ui_manager,
     const scoped_refptr<base::SingleThreadTaskRunner>& io_task_runner,
@@ -137,6 +142,11 @@ void DataReductionProxyDebugBlockingPage::CommandReceived(
   }
 }
 
+content::InterstitialPageDelegate::TypeID
+DataReductionProxyDebugBlockingPage::GetTypeForTesting() const {
+  return DataReductionProxyDebugBlockingPage::kTypeForTesting;
+}
+
 void DataReductionProxyDebugBlockingPage::OnProceed() {
   proceeded_ = true;