[ServiceWorker] Implement WebServiceWorkerContextClient::openWindow().

content/public/browser/content_browser_client.h

Index: content/public/browser/content_browser_client.h
diff --git a/content/public/browser/content_browser_client.h b/content/public/browser/content_browser_client.h
index d2ae7a0dd59c07dd4157d4eb2683965cb4bb539e..5e5d5d4296603604897ba802d38de83c0c8b3b70 100644
--- a/content/public/browser/content_browser_client.h
+++ b/content/public/browser/content_browser_client.h
@@ -108,6 +108,7 @@ class SpeechRecognitionManagerDelegate;
 class WebContents;
 class WebContentsViewDelegate;
 struct MainFunctionParams;
+struct OpenURLParams;
 struct Referrer;
 struct WebPreferences;
 
@@ -614,6 +615,11 @@ class CONTENT_EXPORT ContentBrowserClient {
   virtual PresentationServiceDelegate* GetPresentationServiceDelegate(
       WebContents* web_contents);
 
+  // Allows programmatic opening of a new tab/window without going through
+  // another WebContents. For example, from a Worker.
+  virtual WebContents* OpenURL(BrowserContext* browser_context,
+                               const OpenURLParams& params);
+
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
   // Populates |mappings| with all files that need to be mapped before launching
   // a child process.