Check if there is a SW controlling the start page for app banner.

content/browser/service_worker/service_worker_context_wrapper.cc

Index: content/browser/service_worker/service_worker_context_wrapper.cc
diff --git a/content/browser/service_worker/service_worker_context_wrapper.cc b/content/browser/service_worker/service_worker_context_wrapper.cc
index db0b4e9fffe6c94a3dcb2da3194f3e4629a666a8..d66de442b90217708d9689b54e2547cf38f18bee 100644
--- a/content/browser/service_worker/service_worker_context_wrapper.cc
+++ b/content/browser/service_worker/service_worker_context_wrapper.cc
@@ -21,11 +21,13 @@
 #include "content/browser/service_worker/service_worker_process_manager.h"
 #include "content/browser/service_worker/service_worker_quota_client.h"
 #include "content/browser/service_worker/service_worker_request_handler.h"
+#include "content/browser/service_worker/service_worker_utils.h"
 #include "content/browser/storage_partition_impl.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/service_worker_context.h"
 #include "net/base/net_errors.h"
+#include "net/base/net_util.h"
 #include "net/url_request/url_request_context_getter.h"
 #include "storage/browser/blob/blob_storage_context.h"
 #include "storage/browser/quota/quota_manager_proxy.h"
@@ -278,6 +280,27 @@ void ServiceWorkerContextWrapper::DidGetAllRegistrationsForGetAllOrigins(
   callback.Run(usage_infos);
 }
 
+void ServiceWorkerContextWrapper::DidFindRegistrationForCheckHasServiceWorker(
+    const GURL& other_url,
+    const CheckHasServiceWorkerCallback& callback,
+    ServiceWorkerStatusCode status,
+    const scoped_refptr<ServiceWorkerRegistration>& registration) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+
+  if (status != SERVICE_WORKER_OK) {
+    BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
+                            base::Bind(callback, false));
+    return;
+  }
+
+  DCHECK(registration);
+  BrowserThread::PostTask(
+      BrowserThread::UI, FROM_HERE,
+      base::Bind(callback, registration->active_version() &&
+                               ServiceWorkerUtils::ScopeMatches(
+                                   registration->pattern(), other_url)));
+}
+
 namespace {
 void StatusCodeToBoolCallbackAdapter(
     const ServiceWorkerContext::ResultCallback& callback,
@@ -309,6 +332,30 @@ void ServiceWorkerContextWrapper::DeleteForOrigin(const GURL& origin_url) {
   DeleteForOrigin(origin_url, base::Bind(&EmptySuccessCallback));
 }
 
+void ServiceWorkerContextWrapper::CheckHasServiceWorker(
+    const GURL& url,
+    const GURL& other_url,
+    const CheckHasServiceWorkerCallback& callback) {
+  if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
+    BrowserThread::PostTask(
+        BrowserThread::IO, FROM_HERE,
+        base::Bind(&ServiceWorkerContextWrapper::CheckHasServiceWorker, this,
+                   url, other_url, callback));
+    return;
+  }
+  if (!context_core_.get()) {
+    LOG(ERROR) << "ServiceWorkerContextCore is no longer alive.";
+    BrowserThread::PostTask(BrowserThread::IO, FROM_HERE,
+                            base::Bind(callback, false));
+    return;
+  }
+  GURL stripped_url = net::SimplifyUrlForRequest(url);
+  context()->storage()->FindRegistrationForDocument(
+      stripped_url, base::Bind(&ServiceWorkerContextWrapper::
+                                   DidFindRegistrationForCheckHasServiceWorker,
+                               this, other_url, callback));
+}
+
 void ServiceWorkerContextWrapper::AddObserver(
     ServiceWorkerContextObserver* observer) {
   observer_list_->AddObserver(observer);