R8 full mode by default when RELEASE_R8_FULL_MODE_BY_DEFAULT is enabled

Bug: 215530220
Test: existing
Change-Id: I4360e7ba42a4f27adc347ef3f6fa7511c27366f7
diff --git a/android/config.go b/android/config.go
index 407156d..5b801bc 100644
--- a/android/config.go
+++ b/android/config.go
@@ -2175,6 +2175,10 @@
 	return c.productVariables.GetBuildFlagBool("RELEASE_USE_TRANSITIVE_JARS_IN_CLASSPATH")
 }
 
+func (c *config) UseR8FullModeByDefault() bool {
+	return c.productVariables.GetBuildFlagBool("RELEASE_R8_FULL_MODE_BY_DEFAULT")
+}
+
 func (c *config) UseR8OnlyRuntimeVisibleAnnotations() bool {
 	return c.productVariables.GetBuildFlagBool("RELEASE_R8_ONLY_RUNTIME_VISIBLE_ANNOTATIONS")
 }