Add support for material_blue theme

Add support for material_blue theme, which setup wizard is going to
use for M. This changes SetupWizardUtils.getTheme to always return
either SetupWizardTheme or SetupWizardTheme_Light, and added the
theme value "material" blue.

Bug: 19729981
Change-Id: I63678312af4942be358b92a58b1c84f89aaaa6c1

src/com/android/settings/SetupEncryptionInterstitial.java

@@ -62,7 +62,7 @@ public class SetupEncryptionInterstitial extends EncryptionInterstitial
 
     @Override
     protected void onApplyThemeResource(Resources.Theme theme, int resid, boolean first) {
-        resid = SetupWizardUtils.getTheme(getIntent(), resid);
+        resid = SetupWizardUtils.getTheme(getIntent());
         super.onApplyThemeResource(theme, resid, first);
     }