Add drop shadow to toolbar items in AppDetails.

This is so that feature images with white backgrounds to not completely
obscure the icons.

Fixes #1097.

app/src/main/java/org/fdroid/fdroid/AppDetails2.java

@@ -39,6 +39,7 @@ import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.design.widget.AppBarLayout;
 import android.support.design.widget.CoordinatorLayout;
+import android.support.v4.content.ContextCompat;
 import android.support.v4.content.LocalBroadcastManager;
 import android.support.v7.app.AlertDialog;
 import android.support.v7.app.AppCompatActivity;
@@ -110,6 +111,8 @@ public class AppDetails2 extends AppCompatActivity implements ShareChooserDialog
         setContentView(R.layout.app_details2);
         Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
         toolbar.setTitle(""); // Nice and clean toolbar
+        toolbar.setNavigationIcon(R.drawable.ic_back);
+        toolbar.setOverflowIcon(ContextCompat.getDrawable(this, R.drawable.ic_more));
         setSupportActionBar(toolbar);
         getSupportActionBar().setDisplayHomeAsUpEnabled(true);
         supportPostponeEnterTransition();