Give Doclava our manifest; more permission docs.

We've seen some @SystemApi methods protected with non-system
permissions, so give Doclava the platform AndroidManifest.xml so it
can parse the actual permission protection levels to look for APIs
that are letting in non-system apps.

Also document more @SystemApi permissions.

This is purely a docs change; no logic changes are being made.

Test: make -j32 update-api
Bug: 62263906
Change-Id: Ie0f0a5fb0033817bcc95060f2183a52ae4ae7b06
diff --git a/Android.mk b/Android.mk
index b5f8cb0..3f2ae83 100644
--- a/Android.mk
+++ b/Android.mk
@@ -923,6 +923,7 @@
     -android \
     -knowntags ./frameworks/base/docs/knowntags.txt \
     -knowntags ./libcore/known_oj_tags.txt \
+    -manifest ./frameworks/base/core/res/AndroidManifest.xml \
     -hidePackage com.android.org.conscrypt \
     -since $(SRC_API_DIR)/1.xml 1 \
     -since $(SRC_API_DIR)/2.xml 2 \