build: bump android ndk version

PR-URL: libuv#790
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>

Author: kthelgason

android-configure

@@ -3,7 +3,7 @@
 export TOOLCHAIN=$PWD/android-toolchain
 mkdir -p $TOOLCHAIN
 $1/build/tools/make-standalone-toolchain.sh \
-    --toolchain=arm-linux-androideabi-4.8 \
+    --toolchain=arm-linux-androideabi-4.9 \
     --arch=arm \
     --install-dir=$TOOLCHAIN \
     --platform=android-21
@@ -14,7 +14,7 @@ export CXX=arm-linux-androideabi-g++
 export LINK=arm-linux-androideabi-g++
 export PLATFORM=android
 
-if [ $2 -a $2 == 'gyp' ]
+if [[ $2 == 'gyp' ]]
   then
     ./gyp_uv.py -Dtarget_arch=arm -DOS=android -f make-android
 fi