PlzNavigate: Make ServiceWorker work with PlzNavigate.

content/browser/frame_host/navigator_delegate.h

Index: content/browser/frame_host/navigator_delegate.h
diff --git a/content/browser/frame_host/navigator_delegate.h b/content/browser/frame_host/navigator_delegate.h
index 1494cc339f2ed24e5dcbc75f86475349a36489c1..070e8c76fe7b57e813f84ce286855939f1ffa249 100644
--- a/content/browser/frame_host/navigator_delegate.h
+++ b/content/browser/frame_host/navigator_delegate.h
@@ -17,6 +17,7 @@ struct FrameHostMsg_DidFailProvisionalLoadWithError_Params;
 
 namespace content {
 
+class BrowserContext;
 class FrameTreeNode;
 class NavigationHandle;
 class RenderFrameHostImpl;
@@ -130,6 +131,9 @@ class CONTENT_EXPORT NavigatorDelegate {
 
   // The load progress was changed.
   virtual void DidChangeLoadProgress() {}
+
+  // Helper method to access the BrowserContext.
+  virtual BrowserContext* GetBrowserContext() const;

[michaeln, 2015/10/01 01:42:15]

This method seems out of place on this interface. Most of the method here here
have todo with the navstack telling some outside agency what's happening. This
method is not like that.

[clamy, 2015/10/01 12:41:27]

Agreed. At the end of the day, NavigatorDelegate is about the Navigator
informing the WebContents of the navigation events happening.

[Fabrice (no longer in Chrome), 2015/10/01 18:29:55]

This was the only way I found to access the BrowserContext from the
NavigationHandleImpl that did not result in an access violation somewhere.
This class is implemented as WebContentsImpl, but the presubmit prevent
including the WebContentsImpl header from frame_host (for good reasons), and I
cannot cast the NavigatorDelegate as a WebContents either.
I'd be happy to find another way of handling this.

[clamy, 2015/10/02 10:34:44]

It'd be reasonable to add a pointer to the FTN in the NavigationHandle. From
there you can get the NavigationController that will give you the
BrowserContext.

[Fabrice (no longer in Chrome), 2015/10/02 16:37:34]

Done.

 };
 
 }  // namspace content