Fix crash in ExtensionService::SetIsIncognitoEnabled.

chrome/browser/extensions/extension_service.cc

Index: chrome/browser/extensions/extension_service.cc
diff --git a/chrome/browser/extensions/extension_service.cc b/chrome/browser/extensions/extension_service.cc
index 2499bd4082c69a2e12e81de210a77d276acc9b2b..ef27a9ec750a25ca7de54b1d4a8ec343a60b7280 100644
--- a/chrome/browser/extensions/extension_service.cc
+++ b/chrome/browser/extensions/extension_service.cc
@@ -1456,7 +1456,7 @@ bool ExtensionService::IsIncognitoEnabled(
 }
 
 void ExtensionService::SetIsIncognitoEnabled(
-    const std::string& extension_id, bool enabled) {
+    std::string extension_id, bool enabled) {

[Finnur, 2011/11/10 21:48:44]

I wonder if people will be tempted to change this back to const ref, since it
isn't obvious that a copy is needed and therefore people would look at this as a
potential speedup opportunity? 

Should we document that this must be a copy because callers will likely not make
a copy of the value before calling us?

Or should we take a const ref, but make a copy ourselves (line 1478) before we
reload?

Or should we have the only caller (in this file at least -- are there others?)
make a copy of the ID as well, since we already cache some extension data (line
1409).

Just a thought.

   const Extension* extension = GetInstalledExtension(extension_id);
   if (extension && extension->location() == Extension::COMPONENT) {
     // This shouldn't be called for component extensions.