Is this a bug report?

Yes

Have you read the Contributing Guidelines?

Yes

Environment

Environment:
OS: macOS Sierra 10.12.6
Node: 8.4.0
Yarn: 1.2.1
npm: 5.4.2
Watchman: 4.9.0
Xcode: Xcode 9.1 Build version 9B55
Android Studio: 2.3 AI-162.3934792

Packages: (wanted => installed)
react: 16.0.0-beta.5 => 16.0.0-beta.5
react-native: https://github.com/expo/react-native/archive/sdk-22.0.1.tar.gz => 0.49.3

Target Platform: Android (6.0)

Steps to Reproduce

1. Create a View
2. Give it a style with a non-zero width, backgroundColor, a non-zero borderRadius, a non-zero border_____Width, and a border_____Color that's different from the backgroundColor, where ____ is Top, Bottom, Left, or Right. (can also do multiple sides with colors and widths).
3. Try it on Android.

Expected Behavior

I should see a box with rounded corners with a distinctly-colored border on at least one side.

Actual Behavior

The border is the same color as the box's backgroundColor.

To compare with iOS, where this issue doesn't occur:

Reproducible Demo

Expo Snack demonstrating issue