Add the sun tools to test dependencies.

Change-Id: I0bd5ca8e099ee9b5be3285e645125358026ab0c8
diff --git a/build.gradle b/build.gradle
index dce4a28..9fc38d2 100644
--- a/build.gradle
+++ b/build.gradle
@@ -320,6 +320,7 @@
     keepannoCompile group: 'org.ow2.asm', name: 'asm', version: asmVersion
     keepannoCompile "com.google.guava:guava:$guavaVersion"
     keepannoCompile files("third_party/openjdk/jdk8/linux-x86/lib/tools.jar")
+    testCompile files("third_party/openjdk/jdk8/linux-x86/lib/tools.jar")
     testCompile sourceSets.keepanno.output
     testRuntime sourceSets.keepanno.output
 }