Add methods to retrieve the native CameraMetadata pointer.

Test: atest android.hardware.camera2.cts.CameraManagerTest#testCameraCharacteristicsNdkFromSdk android.hardware.camera2.cts.CaptureResultTest#testCameraCaptureResultAllKeys
Bug: 80513080

Change-Id: I296db8425b562e09843159dfab3afa0960b4854f
2 files changed