add component metadata to all CTS module configs

Bug: 36140955
Bug: 35360169
Test: new unit test to ensure that all modules have this field
Change-Id: Id856f93c0d2a018be65bff33459b4b703d23257d
diff --git a/hostsidetests/compilation/AndroidTest.xml b/hostsidetests/compilation/AndroidTest.xml
index ec92bec..9cc9066 100644
--- a/hostsidetests/compilation/AndroidTest.xml
+++ b/hostsidetests/compilation/AndroidTest.xml
@@ -14,6 +14,7 @@
      limitations under the License.
 -->
 <configuration description="Config for CTS Compilation Test">
+    <option name="config-descriptor:metadata" key="component" value="libcore" />
     <test class="com.android.compatibility.common.tradefed.testtype.JarHostTest" >
         <option name="jar" value="CtsCompilationTestCases.jar" />
         <option name="runtime-hint" value="9m45s" />