Convert //chrome/browser/extensions from scoped_ptr to std::unique_ptr

chrome/browser/extensions/extension_action.cc

Index: chrome/browser/extensions/extension_action.cc
diff --git a/chrome/browser/extensions/extension_action.cc b/chrome/browser/extensions/extension_action.cc
index 86619859667eb7da41071816d26b765031fb4ecf..64e4eabfda89c57ec8ff354781589eb703ff26fc 100644
--- a/chrome/browser/extensions/extension_action.cc
+++ b/chrome/browser/extensions/extension_action.cc
@@ -291,7 +291,7 @@ bool ExtensionAction::HasIcon(int tab_id) const {
 }
 
 void ExtensionAction::SetDefaultIconForTest(
-    scoped_ptr<ExtensionIconSet> default_icon) {
+    std::unique_ptr<ExtensionIconSet> default_icon) {
   default_icon_ = std::move(default_icon);
 }