Revert "Remove desugar support"

This reverts commit 000280bb0e13902b2d19fd102ecf68d0dbbabfba.

Reason for revert: broke art veridex build

Change-Id: I9f7d7cdbe8e34671614687ac0b34c0338ef240e7
diff --git a/java/config/makevars.go b/java/config/makevars.go
index 4dffa02..27c7daa 100644
--- a/java/config/makevars.go
+++ b/java/config/makevars.go
@@ -46,8 +46,15 @@
 	ctx.Strict("JAVADOC", "${JavadocCmd}")
 	ctx.Strict("COMMON_JDK_FLAGS", "${CommonJdkFlags}")
 
-	ctx.Strict("DX", "${D8Cmd}")
-	ctx.Strict("DX_COMMAND", "${D8Cmd} -JXms16M -JXmx2048M")
+	if ctx.Config().UseD8Desugar() {
+		ctx.Strict("DX", "${D8Cmd}")
+		ctx.Strict("DX_COMMAND", "${D8Cmd} -JXms16M -JXmx2048M")
+		ctx.Strict("USE_D8_DESUGAR", "true")
+	} else {
+		ctx.Strict("DX", "${DxCmd}")
+		ctx.Strict("DX_COMMAND", "${DxCmd} -JXms16M -JXmx2048M")
+		ctx.Strict("USE_D8_DESUGAR", "false")
+	}
 	ctx.Strict("R8_COMPAT_PROGUARD", "${R8Cmd}")
 
 	ctx.Strict("TURBINE", "${TurbineJar}")