Use process-per-app-instance for hosted apps without background permission.

content/browser/site_instance_unittest.cc

Index: content/browser/site_instance_unittest.cc
diff --git a/content/browser/site_instance_unittest.cc b/content/browser/site_instance_unittest.cc
index 40b9d8c0823bd83d0e3599c011402eeb6f05b826..48121212c949d2e93dad116527f81c33549df41a 100644
--- a/content/browser/site_instance_unittest.cc
+++ b/content/browser/site_instance_unittest.cc
@@ -42,6 +42,11 @@ class SiteInstanceTestBrowserClient : public content::MockContentBrowserClient {
     return &factory_;
   }
 
+  virtual bool ShouldUseProcessPerSite(Profile* profile,
+                                       const GURL& url) OVERRIDE {
+    return false;
+  }
+
   virtual bool IsURLSameAsAnySiteInstance(const GURL& url) OVERRIDE {
     return url == GURL(kSameAsAnyInstanceURL) ||
            url == GURL(chrome::kAboutCrashURL);