Add ro.bootimage.* property contexts

In addition, allow shell to read this property.

Test: getprop -Z
Test: cts-tradefed run cts -m CtsGestureTestCases
      and check /sdcard/device-info-files/PropertyDeviceInfo.deviceinfo.json

Bug: 169169031
Change-Id: Ib71b01bac326354696e159129f9dea4c2e918c51
diff --git a/private/property_contexts b/private/property_contexts
index 4f7a1dc..9326f45 100644
--- a/private/property_contexts
+++ b/private/property_contexts
@@ -663,6 +663,13 @@
 ro.vendor.build.version.incremental u:object_r:build_vendor_prop:s0 exact string
 ro.vendor.build.version.sdk         u:object_r:build_vendor_prop:s0 exact int
 
+# Boot image build props set by /{second_stage_resources/,}boot/etc/build.prop
+ro.bootimage.build.date                u:object_r:build_bootimage_prop:s0 exact string
+ro.bootimage.build.date.utc            u:object_r:build_bootimage_prop:s0 exact int
+ro.bootimage.build.fingerprint         u:object_r:build_bootimage_prop:s0 exact string
+ro.bootimage.build.version.incremental u:object_r:build_bootimage_prop:s0 exact string
+ro.bootimage.build.version.sdk         u:object_r:build_bootimage_prop:s0 exact int
+
 ro.product.board               u:object_r:build_vendor_prop:s0 exact string
 ro.product.first_api_level     u:object_r:build_vendor_prop:s0 exact int
 ro.product.vendor.brand        u:object_r:build_vendor_prop:s0 exact string