Revert of Remove about:srcdoc url conversion.

content/browser/frame_host/navigation_entry_impl.cc

 // Copyright 2013 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/frame_host/navigation_entry_impl.h"
 
 #include <stddef.h>
 
 #include <queue>
 #include <utility>
@@ skipping 857 matching lines @@
     FrameTreeNode* frame_tree_node) const {
   std::map<std::string, bool> names;
   NavigationEntryImpl::TreeNode* tree_node = FindFrameEntry(frame_tree_node);
   if (tree_node) {
     // Return the names of all immediate children.
     for (TreeNode* child : tree_node->children) {
       // Keep track of whether we would be loading about:blank, since the
       // renderer should be allowed to just commit the initial blank frame if
       // that was the default URL.  PageState doesn't matter there, because
       // content injected into about:blank frames doesn't use it.
-      names[child->frame_entry->frame_unique_name()] =
-          child->frame_entry->url() == url::kAboutBlankURL;
+      //
+      // Be careful not to include iframe srcdoc URLs in this check, which do
+      // need their PageState.  The committed URL in that case gets rewritten to
+      // about:blank, but we can detect it via the PageState's URL.
+      //
+      // See https://crbug.com/657896 for details.
+      bool is_about_blank = false;
+      ExplodedPageState exploded_page_state;
+      if (DecodePageState(child->frame_entry->page_state().ToEncodedData(),
+                          &exploded_page_state)) {
+        ExplodedFrameState frame_state = exploded_page_state.top;
+        if (UTF16ToUTF8(frame_state.url_string.string()) == url::kAboutBlankURL)
+          is_about_blank = true;
+      }
+
+      names[child->frame_entry->frame_unique_name()] = is_about_blank;
     }
   }
   return names;
 }
 
 void NavigationEntryImpl::ClearStaleFrameEntriesForNewFrame(
     FrameTreeNode* frame_tree_node) {
   DCHECK(!frame_tree_node->IsMainFrame());
 
   NavigationEntryImpl::TreeNode* node = nullptr;
@@ skipping 52 matching lines @@
       return node;
 
     // Enqueue any children and keep looking.
     for (auto* child : node->children)
       work_queue.push(child);
   }
   return nullptr;
 }
 
 }  // namespace content