issue #1653: Checking return value for 'native --> jsval'.
issue #1653: Updated the submodule of cxx-generator.
issue #1653: JS_ValueToInt32, JS_ValueToECMAInt32 --> jsval_to_int32
Using JSB_PRECONDITION2 to check the return value of js api.
Reporting an error when binding api return JS_FALSE.
issue #1653: Checking the return value of jsapi. Return JSVAL_VOID if jsapi has no return value.
Merge branch 'gles20' of https://github.com/cocos2d/cocos2d-x into iss1653-jsb-int
Updated cocos2d-js-tests.
issue #1653: Updated the submodule of cxx-generator.
fixed #1653: Using JSB_PRECONDITION2 to check return value in js_bindings_ccbreader.cpp and js_bindings_chipmunk_manual.cpp.
Merge pull request #1831 from dumganhar/iss1653-jsb-int

fixed #1653: Handling correctly when parsing int value in JSB.