Fix NDK r15 undeclared identifier

Signed-off-by: Leo Ma <begeekmyfriend@gmail.com>

app/build.gradle

@@ -9,7 +9,7 @@ android {
         minSdkVersion 16
         targetSdkVersion 22
         versionCode 1
-        versionName "2.5"
+        versionName "2.6"
         ndk {
             abiFilters "armeabi-v7a", "x86"
         }

build.gradle

@@ -5,7 +5,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.3.1'
+        classpath 'com.android.tools.build:gradle:2.3.3'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files

library/build.gradle

@@ -8,7 +8,7 @@ android {
         minSdkVersion 16
         targetSdkVersion 22
         versionCode 1
-        versionName "2.5"
+        versionName "2.6"
 
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
         ndk {

library/src/main/cpp/libenc/libenc.cc

 #include <jni.h>
-
-#include <android/log.h>
+#include <string.h>
 #include <libyuv.h>
 #include <x264.h>
+#include <android/log.h>
+
 #define LIBENC_LOGD(...) ((void)__android_log_print(ANDROID_LOG_DEBUG, "libenc", __VA_ARGS__))
 #define LIBENC_LOGI(...) ((void)__android_log_print(ANDROID_LOG_INFO , "libenc", __VA_ARGS__))
 #define LIBENC_LOGW(...) ((void)__android_log_print(ANDROID_LOG_WARN , "libenc", __VA_ARGS__))