Fix some login error on android

[toshi3221]

Fixes

• Fix Argument Exception when called logout(). 37469f7
  • currentPromise.resolve(new Object()); was called when LineLogin#logout is succeed. But Argument Exception was thrown.
• Fix Exception calling promise multiple times when called another intent callback after calling logout(). 37469f7
  • When intent callback was listened, promise object was called. But the Promise object was not deleted after logging in, then Exception was thrown by being called multiple times when other intent calls.
• Fix exception when the user denied the approval. e6b422a
  • Result code of loginResult when the user denied the approval is AUTHENTICATION_AGENT_ERROR. But NullPointerException was throwed because loginResult was set null.

I comfirmed React Native 0.54.4.

[enrigalmig]

Thanks for your contributions, we will review it and provide feedback 👍 cc: @xmartlabs/react

[santiagofm]

Thanks!