Remove embedded junit src from CTS host.

Instead, CTS will now include junit.jar build from external/junit.
diff --git a/tools/utils/startcts b/tools/utils/startcts
index 00660f7..25f0572 100755
--- a/tools/utils/startcts
+++ b/tools/utils/startcts
@@ -51,11 +51,13 @@
 
 DDM_LIB=${SDK_ROOT}/tools/lib/ddmlib.jar
 CTS_LIB=${CTS_ROOT}/tools/cts.jar
+JUNIT_LIB=${CTS_ROOT}/tools/junit.jar
 ADB_PATH=${SDK_ROOT}/tools
 ADB_EXE=${ADB_PATH}/adb
 
 checkFile ${DDM_LIB}
 checkFile ${CTS_LIB}
+checkFile ${JUNIT_LIB}
 checkFile ${ADB_EXE}
 
 PATH=${ADB_PATH}:${PATH}
@@ -85,4 +87,4 @@
     fi;
 fi;
 
-java ${JAVA_OPTS} -cp ${CTS_LIB}:${DDM_LIB} com.android.cts.TestHost ${CONFIG} "$@" ${DDCONFIG}
+java ${JAVA_OPTS} -cp ${CTS_LIB}:${DDM_LIB}:${JUNIT_LIB} com.android.cts.TestHost ${CONFIG} "$@" ${DDCONFIG}