Allow manifest handlers to declare keys they depend on that must be parsed before them.

chrome/browser/speech/extension_api/tts_extension_api.cc

Index: chrome/browser/speech/extension_api/tts_extension_api.cc
diff --git a/chrome/browser/speech/extension_api/tts_extension_api.cc b/chrome/browser/speech/extension_api/tts_extension_api.cc
index 248f5b2cd416d05a6833786e1d4e39c5f3af708b..7a9ab7aa3b3f3ce68921919ac60ed6e228267afa 100644
--- a/chrome/browser/speech/extension_api/tts_extension_api.cc
+++ b/chrome/browser/speech/extension_api/tts_extension_api.cc
@@ -187,7 +187,7 @@ TtsAPI* TtsAPI::Get(Profile* profile) {
 
 TtsAPI::TtsAPI(Profile* profile) {
   ManifestHandler::Register(extension_manifest_keys::kTtsEngine,
-                            new TtsEngineManifestHandler);
+                            make_linked_ptr(new TtsEngineManifestHandler));
   ExtensionFunctionRegistry* registry =
       ExtensionFunctionRegistry::GetInstance();
   registry->RegisterFunction<ExtensionTtsEngineSendTtsEventFunction>();