Indicate ANGLE is present on devices

The system property ro.gfx.angle.supported needs to be enabled when
ANGLE is included in a build to indicate to the platform and CTS tests
that ANGLE is present on the device.

Test: atest CtsAngleIntegrationHostTestCases
Bug: 157670307
Merged-in: Ide4e3d8f78d3748d557a47ecd153d66694fd1e3a
Change-Id: I72ba8731fed36dbc594dae88aaa00a6299e8f4ae
diff --git a/target/product/base_system.mk b/target/product/base_system.mk
index f6770fb..716f00f 100644
--- a/target/product/base_system.mk
+++ b/target/product/base_system.mk
@@ -352,6 +352,8 @@
 
 PRODUCT_SYSTEM_PROPERTIES += debug.atrace.tags.enableflags=0
 
+PRODUCT_PROPERTY_OVERRIDES += ro.gfx.angle.supported=true
+
 # Packages included only for eng or userdebug builds, previously debug tagged
 PRODUCT_PACKAGES_DEBUG := \
     adb_keys \