Properly catch exceptions

Test: Manual, not defining a default theme in stub provider doesn't crash app
Change-Id: I2b33681cffe8670478687c06667a701bb682cf2f
(cherry picked from commit 10252aa2bf4eaa4b41cced2fe9bd0962f7a61421)
diff --git a/src/com/android/customization/model/theme/DefaultThemeProvider.java b/src/com/android/customization/model/theme/DefaultThemeProvider.java
index ddadc7d..404130f 100644
--- a/src/com/android/customization/model/theme/DefaultThemeProvider.java
+++ b/src/com/android/customization/model/theme/DefaultThemeProvider.java
@@ -188,18 +188,16 @@
             builder.setTitle(mContext.getString(R.string.default_theme_title));
         }
 
-        String colorOverlayPackage = getOverlayPackage(COLOR_PREFIX, DEFAULT_THEME_NAME);
-
         try {
+            String colorOverlayPackage = getOverlayPackage(COLOR_PREFIX, DEFAULT_THEME_NAME);
             mOverlayProvider.addColorOverlay(builder, colorOverlayPackage);
         } catch (NameNotFoundException | NotFoundException e) {
             Log.d(TAG, "Didn't find color overlay for default theme, will use system default");
             mOverlayProvider.addSystemDefaultColor(builder);
         }
 
-        String fontOverlayPackage = getOverlayPackage(FONT_PREFIX, DEFAULT_THEME_NAME);
-
         try {
+            String fontOverlayPackage = getOverlayPackage(FONT_PREFIX, DEFAULT_THEME_NAME);
             mOverlayProvider.addFontOverlay(builder, fontOverlayPackage);
         } catch (NameNotFoundException | NotFoundException e) {
             Log.d(TAG, "Didn't find font overlay for default theme, will use system default");