Revert^2: "Setting Java 11 as the default version"

Reverted Change: I2f9866deff41406aede24758f6eda5e5808c7f29

Reason for revert: Post-submission failure have been fixed.

Test: presubmit
Bug: 195387473
Change-Id: If5db1614ef455e2f1eae1d36cf514e13e7aab993
diff --git a/java/sdk.go b/java/sdk.go
index 756a24d..0dddd40 100644
--- a/java/sdk.go
+++ b/java/sdk.go
@@ -55,14 +55,10 @@
 		return JAVA_VERSION_7
 	} else if sdk.FinalOrFutureInt() <= 29 {
 		return JAVA_VERSION_8
-	} else if ctx.Config().TargetsJava11() {
-		// Temporary experimental flag to be able to try and build with
-		// java version 11 options. The flag, if used, just sets Java
-		// 11 as the default version, leaving any components that
-		// target an older version intact.
-		return JAVA_VERSION_11
-	} else {
+	} else if sdk.FinalOrFutureInt() <= 31 {
 		return JAVA_VERSION_9
+	} else {
+		return JAVA_VERSION_11
 	}
 }