Implement updateViaCache flag and no-cache by default for main service worker scripts

third_party/WebKit/Source/modules/serviceworkers/ServiceWorkerRegistration.cpp

Index: third_party/WebKit/Source/modules/serviceworkers/ServiceWorkerRegistration.cpp
diff --git a/third_party/WebKit/Source/modules/serviceworkers/ServiceWorkerRegistration.cpp b/third_party/WebKit/Source/modules/serviceworkers/ServiceWorkerRegistration.cpp
index 7513bbb092d5bb791ce7f32f702d52be504ab967..0a653754002305d140c935316157a7a4da72e42f 100644
--- a/third_party/WebKit/Source/modules/serviceworkers/ServiceWorkerRegistration.cpp
+++ b/third_party/WebKit/Source/modules/serviceworkers/ServiceWorkerRegistration.cpp
@@ -88,6 +88,21 @@ String ServiceWorkerRegistration::scope() const {
   return handle_->Registration()->Scope().GetString();
 }
 
+String ServiceWorkerRegistration::updateViaCache() const {
+  switch (handle_->Registration()->UpdateViaCache()) {
+    case WebServiceWorkerUpdateViaCache::kImports:
+      return "imports";
+    case WebServiceWorkerUpdateViaCache::kAll:
+      return "all";
+    case WebServiceWorkerUpdateViaCache::kNone:
+      return "none";
+    case WebServiceWorkerUpdateViaCache::kUnknown:
+      break;
+  }
+  NOTREACHED();
+  return "imports";
+}
+
 ScriptPromise ServiceWorkerRegistration::update(ScriptState* script_state) {
   ServiceWorkerContainerClient* client =
       ServiceWorkerContainerClient::From(GetExecutionContext());