Camera: Document 3.4 metadata selection logic.

Bug: 119575429
Test: Ensure everything still builds.
Change-Id: I6500ab06b8c392310009ecfa0570000742fd069c
diff --git a/current.txt b/current.txt
index beafcf0..eb73b57 100644
--- a/current.txt
+++ b/current.txt
@@ -388,7 +388,7 @@
 2a55e224aa9bc62c0387cd85ad3c97e33f0c33a4e1489cbae86b2523e6f9df35 android.hardware.camera.device@3.2::ICameraDevice
 8caf9104dc6885852c0b117d853dd93f6d4b61a0a365138295eb8bcd41b36423 android.hardware.camera.device@3.2::ICameraDeviceSession
 684702a60deef03a1e8093961dc0a18c555c857ad5a77ba7340b0635ae01eb70 android.hardware.camera.device@3.4::ICameraDeviceSession
-e96190f635b8458b92525bd6e040fec4ccbac22fdd4bc7274a9794ab976362f7 android.hardware.camera.device@3.4::types
+f8a19622cb0cc890913b1ef3e32b675ffb26089a09e02fef4056ebad324d2b5d android.hardware.camera.device@3.4::types
 291638a1b6d4e63283e9e722ab5049d9351717ffa2b66162124f84d1aa7c2835 android.hardware.camera.metadata@3.2::types
 8a075cf3a17fe99c6d23415a3e9a65612f1fee73ee052a3a8a0ca5b8877395a4 android.hardware.camera.metadata@3.3::types
 da33234403ff5d60f3473711917b9948e6484a4260b5247acdafb111193a9de2 android.hardware.configstore@1.0::ISurfaceFlingerConfigs