Use Drawer in Settings app

- get rid of PreferenceActivity as much as we can and use fragments instead
- add Drawer widget
- add Dashboard high level entry into the Drawer (but this is work in progress and would be done in another CL)
- add bypass of fragment's Header  validation when launched from the Drawer but *force* validation if external
call thru an Intent

Be aware that WifiPickerActivity should remain for now a PreferenceActivity. It is used by SetupWizard and should
not trigger running the SettingsActivity's header building code. SetupWizard is a Home during the provisionnig process
and then deactivate itself as a Home but would make the Home header to appear in the Drawer (because momentarily we
would have two Home).

Also, verified that:

- the WiFi settings still work when called from SetupWizard
- when you have multiple Launchers, the Home header will appear in the list of Headers in the Drawer

Change-Id: I407a5e0fdd843ad7615d3d511c416a44e3d97c90

src/com/android/settings/tts/TtsEnginePreference.java

@@ -22,7 +22,6 @@ import android.content.DialogInterface;
 import android.content.Intent;
 import android.os.Bundle;
 import android.preference.Preference;
-import android.preference.PreferenceActivity;
 import android.speech.tts.TextToSpeech.EngineInfo;
 import android.util.Log;
 import android.view.View;
@@ -33,6 +32,7 @@ import android.widget.RadioButton;
 
 
 import com.android.settings.R;
+import com.android.settings.SettingsActivity;
 import com.android.settings.Utils;
 
 
@@ -63,7 +63,7 @@ public class TtsEnginePreference extends Preference {
      * The preference activity that owns this preference. Required
      * for instantiating the engine specific settings screen.
      */
-    private final PreferenceActivity mPreferenceActivity;
+    private final SettingsActivity mSettingsActivity;
 
     /**
      * The engine information for the engine this preference represents.
@@ -95,12 +95,12 @@ public class TtsEnginePreference extends Preference {
         };
 
     public TtsEnginePreference(Context context, EngineInfo info, RadioButtonGroupState state,
-            PreferenceActivity prefActivity) {
+            SettingsActivity prefActivity) {
         super(context);
         setLayoutResource(R.layout.preference_tts_engine);
 
         mSharedState = state;
-        mPreferenceActivity = prefActivity;
+        mSettingsActivity = prefActivity;
         mEngineInfo = info;
         mPreventRadioButtonCallbacks = false;
 
@@ -156,10 +156,10 @@ public class TtsEnginePreference extends Preference {
                 }
 
                 // Note that we use this instead of the (easier to use)
-                // PreferenceActivity.startPreferenceFragment because the
+                // SettingsActivity.startPreferenceFragment because the
                 // title will not be updated correctly in the fragment
                 // breadcrumb since it isn't inflated from the XML layout.
-                mPreferenceActivity.startPreferencePanel(
+                mSettingsActivity.startPreferencePanel(
                         TtsEngineSettingsFragment.class.getName(),
                         args, 0, mEngineInfo.label, null, 0);
             }