Fix for "chrome://" links in PDFs.

chrome/browser/extensions/chrome_extension_web_contents_observer.cc

 // Copyright 2014 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 "chrome/browser/extensions/chrome_extension_web_contents_observer.h"
 
 #include "chrome/browser/extensions/error_console/error_console.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/window_controller.h"
 #include "chrome/common/extensions/chrome_extension_messages.h"
+#include "chrome/common/url_constants.h"
 #include "content/public/browser/browser_context.h"
+#include "content/public/browser/child_process_security_policy.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "extensions/browser/extension_registry.h"
 #include "extensions/browser/extension_system.h"
 #include "extensions/common/extension_messages.h"
 #include "extensions/common/extension_urls.h"
 
 using content::BrowserContext;
 
 DEFINE_WEB_CONTENTS_USER_DATA_KEY(
     extensions::ChromeExtensionWebContentsObserver);
 
 namespace extensions {
 
 ChromeExtensionWebContentsObserver::ChromeExtensionWebContentsObserver(
     content::WebContents* web_contents)
     : ExtensionWebContentsObserver(web_contents) {}
 
 ChromeExtensionWebContentsObserver::~ChromeExtensionWebContentsObserver() {}
 
 void ChromeExtensionWebContentsObserver::RenderViewCreated(
     content::RenderViewHost* render_view_host) {
   ReloadIfTerminated(render_view_host);
   ExtensionWebContentsObserver::RenderViewCreated(render_view_host);
+
+  const Extension* extension = GetExtension(render_view_host);
+  if (!extension)
+    return;
+
+  int process_id = render_view_host->GetProcess()->GetID();
+  auto policy = content::ChildProcessSecurityPolicy::GetInstance();
+
+  // Components of chrome that are implemented as extensions are allowed to use
+  // chrome://resources/ URLs.
+  if (extension->is_extension() &&
+      Manifest::IsComponentLocation(extension->location())) {
+    std::string origin_url;
+    base::SStringPrintf(&origin_url, "%s://%s/", content::kChromeUIScheme,

[Devlin, 2015/09/29 19:06:30]

And, both those said, I actually wouldn't be opposed to just adding a
chrome::kChromeUIResourcesURL, but I'll defer to other people's opinions there.

[Devlin, 2015/09/29 19:06:30]

nit: Why SStringPrintf, instead of just StringPrintf?

[Devlin, 2015/09/29 19:06:30]

nit: Also kStandardSchemeSeparator

[Charlie Reis, 2015/09/29 22:15:53]

I'd be happy with that, similar to kChromeUINetworkViewCacheURL and 
kChromeUINetworkViewCacheHost.

[paulmeyer, 2015/09/30 14:21:31]

Done.

[paulmeyer, 2015/09/30 14:21:31]

No particular reason, but I'm taking it out anyways.

[paulmeyer, 2015/09/30 14:21:31]

Done.

[paulmeyer, 2015/09/30 14:21:31]

Acknowledged.

+                        content::kChromeUIResourcesHost);
+    policy->GrantOrigin(process_id, url::Origin(GURL(origin_url)));
+  }
+
+  // Extensions, legacy packaged apps, and component platform apps are allowed
+  // to use chrome://favicon/ and chrome://extension-icon/ URLs. Hosted apps are
+  // not allowed because they are served via web servers (and are generally
+  // never given access to Chrome APIs).
+  if (extension->is_extension() ||
+      extension->is_legacy_packaged_app() ||
+      (extension->is_platform_app() &&
+       Manifest::IsComponentLocation(extension->location()))) {
+    policy->GrantOrigin(process_id,
+                        url::Origin(GURL(chrome::kChromeUIFaviconURL)));
+    policy->GrantOrigin(process_id,
+                        url::Origin(GURL(chrome::kChromeUIExtensionIconURL)));
+  }
 }
 
 bool ChromeExtensionWebContentsObserver::OnMessageReceived(
     const IPC::Message& message,
     content::RenderFrameHost* render_frame_host) {
   if (ExtensionWebContentsObserver::OnMessageReceived(message,
                                                       render_frame_host)) {
     return true;
   }
 
@@ skipping 51 matching lines @@
   // TODO(yoz): This reload doesn't happen synchronously for unpacked
   //            extensions. It seems to be fast enough, but there is a race.
   //            We should delay loading until the extension has reloaded.
   if (registry->GetExtensionById(extension_id, ExtensionRegistry::TERMINATED)) {
     ExtensionSystem::Get(browser_context())->
         extension_service()->ReloadExtension(extension_id);
   }
 }
 
 }  // namespace extensions