Settings - update for new UI (no more Drawer)

- follow the UX spec by no more using a Drawer
- the Dashboard is now a Fragment that contains the list of Headers
- the search results are also put into a Fragment that is replacing
the initial one (Dashboard or other) when expanding the SearchView
- use a SearchView for query input
- when tapping on a Header or a Search Result, re-launch Settings as
an Activity so that we are benefiting from the Activity stack for
UP affordance and BACK button
- manage UP affordance to show it only when needed
- move some Actions to the Menu in the ActionBar for allowing space
to the Search action and removing some clutter
- fix an issue with the Index and WiFiEnabler and their cached Context
that was not updated when there was a Configuration change
- simplify the SettingsActivity code by extracting some inner classes

Change-Id: I50b5f77bb44a7fade1886114dbbc820609a5e63d

src/com/android/settings/bluetooth/BluetoothSettings.java

@@ -129,7 +129,7 @@ public final class BluetoothSettings extends DeviceListPreferenceFragment implem
 
         final SettingsActivity activity = (SettingsActivity) getActivity();
 
-        if (!activity.onIsHidingHeaders()) {
+        if (activity.onIsHidingHeaders()) {
             activity.getActionBar().setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM,
                     ActionBar.DISPLAY_SHOW_CUSTOM);
             activity.getActionBar().setCustomView(mSwitch, new ActionBar.LayoutParams(
@@ -198,7 +198,7 @@ public final class BluetoothSettings extends DeviceListPreferenceFragment implem
             R.string.bluetooth_search_for_devices;
         menu.add(Menu.NONE, MENU_ID_SCAN, 0, textId)
                 .setEnabled(bluetoothIsEnabled && !isDiscovering)
-                .setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM);
+                .setShowAsAction(MenuItem.SHOW_AS_ACTION_NEVER);
         menu.add(Menu.NONE, MENU_ID_RENAME_DEVICE, 0, R.string.bluetooth_rename_device)
                 .setEnabled(bluetoothIsEnabled)
                 .setShowAsAction(MenuItem.SHOW_AS_ACTION_NEVER);