Use "-j8" flag to ndk-build when building TestJavaScript

* If a "-p" for "parallel build" option is set

samples/TestJavascript/proj.android/build_native.sh

@@ -3,6 +3,7 @@ APPNAME="TestJavascript"
 # options
 
 buildexternalsfromsource=
+PARALLEL_BUILD_FLAG=
 
 usage(){
 cat << EOF
@@ -12,15 +13,19 @@ Build C/C++ code for $APPNAME using Android NDK
 
 OPTIONS:
 -s	Build externals from source
+-p  Run make with -j8 option to take advantage of multiple processors
 -h	this help
 EOF
 }
 
-while getopts "sh" OPTION; do
+while getopts "sph" OPTION; do
 case "$OPTION" in
 s)
 buildexternalsfromsource=1
 ;;
+p)
+PARALLEL_BUILD_FLAG=\-j8
+;;
 h)
 usage
 exit 0
@@ -90,6 +95,6 @@ echo
 
 set -x
 
-"$NDK_ROOT"/ndk-build -C "$APP_ANDROID_ROOT" $* \
+"$NDK_ROOT"/ndk-build $PARALLEL_BUILD_FLAG -C "$APP_ANDROID_ROOT" $* \
     "NDK_MODULE_PATH=${COCOS2DX_ROOT}:${COCOS2DX_ROOT}/cocos2dx/platform/third_party/android/prebuilt" \
     NDK_LOG=1 V=1