compiled failed

[XiaNaLee]

/develop/android/githubSource/weex_js_engine/jni/v8core/com_taobao_weex_bridge_WXBridge.cpp:123:37: error: 
      use of undeclared identifier 'strlen'
    v8::V8::SetFlagsFromString(str, strlen(str));
                                    ^
/develop/android/githubSource/weex_js_engine/jni/v8core/com_taobao_weex_bridge_WXBridge.cpp:403:22: error: 
      use of undeclared identifier 'strlen'
        int strLen = strlen(ToCString(str));
                     ^
/develop/android/githubSource/weex_js_engine/jni/v8core/com_taobao_weex_bridge_WXBridge.cpp:411:22: error: 
      use of undeclared identifier 'strlen'
        int strLen = strlen(*tasks);
                     ^
/develop/android/githubSource/weex_js_engine/jni/v8core/com_taobao_weex_bridge_WXBridge.cpp:470:22: error: 
      use of undeclared identifier 'strlen'
        int strLen = strlen(ToCString(str));
                     ^

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