Add context overload

Change-Id: Ieb1c289837cedc63e0b8c79c8034ac88301df4b1

Author: samtstern

auth/src/main/java/com/firebase/ui/auth/AuthUI.java

@@ -21,6 +21,7 @@
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.annotation.StyleRes;
+import android.support.annotation.VisibleForTesting;
 
 import com.facebook.FacebookSdk;
 import com.facebook.login.LoginManager;
@@ -416,6 +417,11 @@ public SignInIntentBuilder setIsSmartLockEnabled(boolean enabled) {
 
         public Intent build() {
             Context context = mApp.getApplicationContext();
+            return build(context);
+        }
+
+        @VisibleForTesting
+        public Intent build(Context context) {
             List<IDPProviderParcel> providerInfo =
                     ProviderHelper.getProviderParcels(context, mProviders);
             return ChooseAccountActivity.createIntent(

auth/src/test/java/com/firebase/ui/auth/ui/ChooseAccountActivityTest.java

@@ -73,7 +73,7 @@ private Intent createStartIntent() {
                 .createSignInIntentBuilder()
                 .setProviders(AuthUI.EMAIL_PROVIDER, AuthUI.GOOGLE_PROVIDER)
                 .setIsSmartLockEnabled(true)
-                .build();
+                .build(RuntimeEnvironment.application);
     }
 
     @Test