Implementation of the "Redirect URLs to Packaged Apps" feature.

chrome/browser/ui/browser_navigator.cc

Index: chrome/browser/ui/browser_navigator.cc
diff --git a/chrome/browser/ui/browser_navigator.cc b/chrome/browser/ui/browser_navigator.cc
index fb73fe7d6191e54d1d4abd8e98c1bbc8ab3a86c7..2f50d8e42cabeb24d4a9dbb8f5a79e03c96e3304 100644
--- a/chrome/browser/ui/browser_navigator.cc
+++ b/chrome/browser/ui/browser_navigator.cc
@@ -458,9 +458,14 @@ void Navigate(NavigateParams* params) {
     return;
 
   ExtensionService* service = params->initiating_profile->GetExtensionService();
-  if (service)
+  if (service) {
+    // TODO(sergeygs): Shouldn't we return from here if this returns true?

[not at google - send to devlin, 2013/08/19 23:32:24]

no, it looks like this method modifies the URL to point to an error page.

[sergeygs, 2013/08/29 08:24:42]

Done.

     service->ShouldBlockUrlInBrowserTab(&params->url);
 
+    if (service->MaybeRedirectUrlToApp(params->url, params->referrer.url))
+      return;
+  }

[not at google - send to devlin, 2013/08/19 23:32:24]

when you pull the MaybeRedirecturlToApp logic out of ExtensionService, you could
make it an abstraction for platform app redirection. this could be like:

// would be nice to add an AppSystem and use that rather than ExtensionSystem.
extensions::PlatformAppRedirector* platform_app_redirector =
    extensions::ExtensionSystem::Get(params->initiating_profile)->
        platform_app_redirector();

if (platform_app_redirector->HandleUrl(params->url,
                                       params->referrer.url,
                                       &params->url))
  return;

[sergeygs, 2013/08/29 08:24:42]

Done. Would it make sense to also obtain the ExtensionService as
system->extension_service() now, for symmetry and minimizing local variables?

[not at google - send to devlin, 2013/08/29 17:35:56]

yeah that would be nice. You could restructure this part nicely:

ExtenisonSystem* system = ...;
if (system && !system->extension_service()->ShouldBlockUrlInBrowserTab()) {
  // ...
}

writing that snippet made me wonder whether we should only check the platform
app redirector if the extension service didn't rewrite the URL. It doesn't make
any sense for the platform app redirector to be handling error URLs.

[sergeygs, 2013/08/30 00:39:44]

Done. The second part didn't occur to me, but sounds like a reasonable idea.

+
   // The browser window may want to adjust the disposition.
   if (params->disposition == NEW_POPUP &&
       source_browser &&