Revert "Automatically trigger installation of high-quality speech synthesis extension."

chrome/browser/speech/tts_chromeos.cc

 // Copyright (c) 2012 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 "base/bind_helpers.h"
-#include "base/logging.h"
-#include "base/prefs/scoped_user_pref_update.h"
-#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/speech/tts_extension_loader_chromeos.h"
 #include "chrome/browser/speech/tts_platform.h"
-#include "chrome/common/extensions/extension_constants.h"
-#include "chrome/common/pref_names.h"
-
-namespace {
-
-// Trigger installing high-quality speech after this many utterances
-// have been spoken in one session.
-const int kHighQualitySpeechUtteranceThreshold = 100;
-
-}  // anonymous namespace
 
 // Chrome OS doesn't have native TTS, instead it includes a built-in
-// component extension that provides speech synthesis. This class monitors
-// use of this component extension and triggers installing a higher-quality
-// speech synthesis extension if a certain number of utterances are spoken
-// in a single session.
+// component extension that provides speech synthesis. This class includes
+// an implementation of LoadBuiltInTtsExtension and dummy implementations of
+// everything else.
 class TtsPlatformImplChromeOs
     : public TtsPlatformImpl {
  public:
   // TtsPlatformImpl overrides:
   virtual bool PlatformImplAvailable() OVERRIDE {
     return false;
   }
 
+  virtual bool LoadBuiltInTtsExtension(Profile* profile) OVERRIDE {
+    return TtsExtensionLoaderChromeOs::GetInstance(profile)->LoadTtsExtension();
+  }
+
   virtual bool Speak(
       int utterance_id,
       const std::string& utterance,
       const std::string& lang,
       const VoiceData& voice,
       const UtteranceContinuousParameters& params) OVERRIDE {
     return false;
   }
 
-  virtual bool StopSpeaking() OVERRIDE { return false; }
+  virtual bool StopSpeaking() OVERRIDE {
+    return false;
+  }
+
   virtual void Pause() OVERRIDE {}
+
   virtual void Resume() OVERRIDE {}
-  virtual bool IsSpeaking() OVERRIDE { return false; }
-  virtual void GetVoices(std::vector<VoiceData>* out_voices) OVERRIDE {}
 
-  virtual void WillSpeakUtteranceWithVoice(
-      const Utterance* utterance,
-      const VoiceData& voice_data) OVERRIDE;
+  virtual bool IsSpeaking() OVERRIDE {
+    return false;
+  }
+
+  virtual void GetVoices(std::vector<VoiceData>* out_voices) OVERRIDE {
+  }
 
   // Get the single instance of this class.
   static TtsPlatformImplChromeOs* GetInstance();
 
  private:
-  TtsPlatformImplChromeOs();
+  TtsPlatformImplChromeOs() {}
   virtual ~TtsPlatformImplChromeOs() {}
 
   friend struct DefaultSingletonTraits<TtsPlatformImplChromeOs>;
 
-  // A count of the number of utterances spoken for each language
-  // using the built-in speech synthesis. When enough utterances have
-  // been spoken in a single session, automatically enable install
-  // the high-quality speech synthesis extension for that language.
-  base::hash_map<std::string, int> lang_utterance_count_;
-
   DISALLOW_COPY_AND_ASSIGN(TtsPlatformImplChromeOs);
 };
 
-TtsPlatformImplChromeOs::TtsPlatformImplChromeOs() {
-}
-
-void TtsPlatformImplChromeOs::WillSpeakUtteranceWithVoice(
-    const Utterance* utterance,
-    const VoiceData& voice_data) {
-  CHECK(utterance);
-  CHECK(utterance->profile());
-
-  if (utterance->profile()->IsOffTheRecord())
-    return;
-
-  if (voice_data.extension_id != extension_misc::kSpeechSynthesisExtensionId)
-    return;
-
-  lang_utterance_count_[voice_data.lang]++;
-  if (lang_utterance_count_[voice_data.lang] !=
-          kHighQualitySpeechUtteranceThreshold) {
-    return;
-  }
-
-  // Add this language to the list that are allowed to install a
-  // component extension for high-quality speech synthesis, overriding
-  // the lower-quality one.
-  ListPrefUpdate updater(utterance->profile()->GetPrefs(),
-                         prefs::kHighQualitySpeechSynthesisLanguages);
-  updater->AppendIfNotPresent(new base::StringValue(voice_data.lang));
-}
-
 // static
 TtsPlatformImpl* TtsPlatformImpl::GetInstance() {
   return TtsPlatformImplChromeOs::GetInstance();
 }
 
 // static
 TtsPlatformImplChromeOs*
 TtsPlatformImplChromeOs::GetInstance() {
   return Singleton<TtsPlatformImplChromeOs>::get();
 }