Remove about:srcdoc url conversion.

content/browser/site_instance_impl.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/site_instance_impl.h"
 
 #include "content/browser/browsing_instance.h"
 #include "content/browser/child_process_security_policy_impl.h"
 #include "content/browser/frame_host/debug_urls.h"
 #include "content/browser/frame_host/frame_tree_node.h"
@@ skipping 298 matching lines @@
   // Some special URLs will match the site instance of any other URL. This is
   // done before checking both of them for validity, since we want these URLs
   // to have the same site instance as even an invalid one.
   if (IsRendererDebugURL(src_url) || IsRendererDebugURL(dest_url))
     return true;
 
   // If either URL is invalid, they aren't part of the same site.
   if (!src_url.is_valid() || !dest_url.is_valid())
     return false;
 
-  // If the destination url is just a blank page, we treat them as part of the
-  // same site.
-  GURL blank_page(url::kAboutBlankURL);
-  if (dest_url == blank_page)
+  // If the destination url is just about:blank or about:srcdoc, we treat them
+  // as part of the same site.
+  if (dest_url == url::kAboutBlankURL || dest_url == content::kAboutSrcDocURL)

[Charlie Reis, 2016/11/22 01:01:20]

Let's leave this out.  As I mentioned in a previous patchset, I think we're
already doing the right thing by letting RFHM handle it, and I worry that this
could introduce a problem.  (For example, if a parent frame tells an OOPIF to go
to a srcdoc, it should join the parent's process and not stay in whatever
process it was in before.)

[arthursonzogni, 2016/11/22 16:43:27]

I add a test in a separate CL:
https://codereview.chromium.org/2525433003/

FYI: the test passes with this CL. But I will still remove this part in case
there are other problems.

     return true;
 
   // If the schemes differ, they aren't part of the same site.
   if (src_url.scheme() != dest_url.scheme())
     return false;
 
   return net::registry_controlled_domains::SameDomainOrHost(
       src_url,
       dest_url,
       net::registry_controlled_domains::INCLUDE_PRIVATE_REGISTRIES);
@@ skipping 107 matching lines @@
             browsing_instance_->browser_context(), site_))
       return;
 
     ChildProcessSecurityPolicyImpl* policy =
         ChildProcessSecurityPolicyImpl::GetInstance();
     policy->LockToOrigin(process_->GetID(), site_);
   }
 }
 
 }  // namespace content