Transfer user agent override info between browser and renderer

content/public/browser/navigation_controller.h

Index: content/public/browser/navigation_controller.h
diff --git a/content/public/browser/navigation_controller.h b/content/public/browser/navigation_controller.h
index c9c1a01384a76cd56736af5fe1bc2e9e5c4ec4fd..7cf6fdf5c2dcc8abcd7537f514443768c8ef90a9 100644
--- a/content/public/browser/navigation_controller.h
+++ b/content/public/browser/navigation_controller.h
@@ -167,6 +167,15 @@ class NavigationController {
                                    PageTransition type,
                                    const std::string& extra_headers) = 0;
 
+  // Same as LoadURL, but allows overriding the user agent of the
+  // NavigationEntry before it loads.
+  virtual void LoadURLWithUserAgentOverride(const GURL& url,

[darin (slow to review), 2012/06/19 18:36:34]

it feels like we might be getting to the point where there should be a single
LoadURL function that takes a parameters class.  dunno.

[gone, 2012/06/19 21:44:22]

Yeah, there's some discussion on the interfaces being added in
https://chromiumcodereview.appspot.com/10544175/.  It seems like all the
functions are trying to work around having to add custom parameters to the
NavigationEntry before it gets sent off.

[Charlie Reis, 2012/06/19 22:47:59]

I think I agree.  LoadURLWithUserAgentOverride now has a is_renderer_initiated
parameter, so it supersedes LoadURL and LoadURLFromRenderer.  Even if we didn't
add a parameters class yet, I bet we could rename this one to LoadURL and
replace the other two.

(Then again, that might touch a ton of code.  If so, maybe it could be left for
a follow-up CL?)

[gone, 2012/06/20 00:01:10]

Yeah, if this replaces LoadURL, it should definitely be done as a follow up CL;
the current LoadURL() is called from all over the place.

[Charlie Reis, 2012/06/20 00:17:52]

Sure.  Maybe just add a TODO for now, to be sure it doesn't get forgotten.

+                                            const Referrer& referrer,
+                                            PageTransition type,
+                                            bool is_renderer_initiated,
+                                            const std::string& extra_headers,
+                                            bool is_overriding_user_agent) = 0;
+
   // Behaves like LoadURL() and LoadURLFromRenderer() but marks the new
   // navigation as being transferred from one RVH to another. In this case the
   // browser can recycle the old request once the new renderer wants to