Android: Add support for unified headers
The unified headers are preferred as of NDK r15, so use them by default if available and provide an option to use the deprecated headers.
Supersedes: !492 (closed)
Fixes: #16584 (closed)
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The unified headers are preferred as of NDK r15, so use them by default if available and provide an option to use the deprecated headers.
Supersedes: !492 (closed)
Fixes: #16584 (closed)