Contributed by Eriq Augustine <eriq.augustine@gmail.com>

chrome/browser/extensions/extension_menu_manager.cc

Index: chrome/browser/extensions/extension_menu_manager.cc
===================================================================
--- chrome/browser/extensions/extension_menu_manager.cc	(revision 116264)
+++ chrome/browser/extensions/extension_menu_manager.cc	(working copy)
@@ -139,8 +139,13 @@
   context_items_[extension_id].push_back(item);
   items_by_id_[item->id()] = item;
 
-  if (item->type() == ExtensionMenuItem::RADIO && item->checked())
-    RadioItemSelected(item);
+  if (item->type() == ExtensionMenuItem::RADIO) {
+    if (item->checked()) {
+      RadioItemSelected(item);
+    } else {
+      SanitizeRadioList(context_items_[extension_id]);
+    }
+  }

[asargent_no_longer_on_chrome, 2012/01/06 21:17:42]

nit: other code uses the optional style practice of omitting braces for
single-line bodies of if statements, so yours should follow that too (here and
in your other edits in the file). E.g.

if (condition)
  foo();
else
  bar();

instead of:

if (condition) {
  foo();
} else {
  bar();
}

 
   // If this is the first item for this extension, start loading its icon.
   if (first_item)
@@ -158,6 +163,11 @@
     return false;
   parent->AddChild(child);
   items_by_id_[child->id()] = child;
+
+  if (child->type() == ExtensionMenuItem::RADIO) {
+    SanitizeRadioList(parent->children());
+  }
+
   return true;
 }
 
@@ -201,6 +211,7 @@
     ExtensionMenuItem* taken =
       old_parent->ReleaseChild(child_id, false /* non-recursive search*/);
     DCHECK(taken == child);
+    SanitizeRadioList(old_parent->children());
   } else {
     // This is a top-level item, so we need to pull it out of our list of
     // top-level items.
@@ -217,13 +228,16 @@
       return false;
     }
     list.erase(j);
+    SanitizeRadioList(list);
   }
 
   if (new_parent) {
     new_parent->AddChild(child);
+    SanitizeRadioList(new_parent->children());
   } else {
     context_items_[child->extension_id()].push_back(child);
     child->parent_id_.reset(NULL);
+    SanitizeRadioList(context_items_[child->extension_id()]);
   }
   return true;
 }
@@ -254,6 +268,7 @@
       delete *j;
       list.erase(j);
       result = true;
+      SanitizeRadioList(list);
       break;
     } else {
       // See if the item to remove was found as a descendant of the current
@@ -262,6 +277,7 @@
       if (child) {
         items_removed = child->RemoveAllDescendants();
         items_removed.insert(id);
+        SanitizeRadioList(GetItemById(*child->parent_id())->children());
         delete child;
         result = true;
         break;
@@ -449,6 +465,64 @@
       item->extension_id(), event_name, json_args, profile, GURL());
 }
 
+void ExtensionMenuManager::SanitizeRadioList(
+    const ExtensionMenuItem::List& item_list) {
+  ExtensionMenuItem::List::const_iterator i = item_list.begin();
+  while (i != item_list.end()) {
+    if ((*i)->type() == ExtensionMenuItem::RADIO) {

[asargent_no_longer_on_chrome, 2012/01/06 21:17:42]

nit: you could improve readability slightly by making an early out for the
non-radio case. E.g.

while (i != item_list.end()) {
  if ((*i)->type() != ExtensionMenuItem::RADIO) {
    ++i;
    break;
  }
  ... rest of code, now indented one level less ...
}

+      // If there are multiple items selected, the last one will override the
+      // others.
+      ExtensionMenuItem::List::const_iterator last_checked = item_list.end();
+      ExtensionMenuItem::List::const_iterator radio_run_iter;
+      for (radio_run_iter = i; radio_run_iter != item_list.end();
+          ++radio_run_iter) {
+        if ((*radio_run_iter)->type() != ExtensionMenuItem::RADIO) {
+          break;
+        }
+
+        if ((*radio_run_iter)->checked()) {
+          last_checked = radio_run_iter;
+          (*radio_run_iter)->SetChecked(false);
+        }
+      }
+
+      // If radio items were found in this run,
+      // check the first radio item in the list (i).

[asargent_no_longer_on_chrome, 2012/01/06 21:17:42]

nit: this comment isn't quite right. It could be something like: "Reset the last
checked item we found to checked. If we didn't find any checked items, set the
first one to checked."

Alternatively, you could just modify the comment several lines above to be
something like "Uncheck any checked radio items in the run, and at the end reset
the appropriate one to checked."

+      if (last_checked != item_list.end()) {
+        (*last_checked)->SetChecked(true);
+      } else {
+        (*i)->SetChecked(true);
+      }
+
+      i = radio_run_iter;
+    } else {
+      ++i;
+    }
+  }
+}
+
+bool ExtensionMenuManager::ItemUpdated(const ExtensionMenuItem::Id& id) {
+  if (!ContainsKey(items_by_id_, id))
+    return false;
+
+  ExtensionMenuItem* menu_item = GetItemById(id);
+  DCHECK(menu_item);
+
+  if (menu_item->parent_id()) {
+    SanitizeRadioList(GetItemById(*menu_item->parent_id())->children());
+  } else {
+    std::string extension_id = menu_item->extension_id();
+    MenuItemMap::iterator i = context_items_.find(extension_id);
+    if (i == context_items_.end()) {
+      NOTREACHED();
+      return false;
+    }
+    SanitizeRadioList(i->second);
+  }
+
+  return true;
+}
+
 void ExtensionMenuManager::Observe(
     int type,
     const content::NotificationSource& source,