Support multi account operation for Android.

[masahiro-ikemoto]

Android can deal with multiple google accounts, but the helth plugin only targets the last signed in account. So I extend the plugin to support multiple google accounts, and update example to check following changes.

• Add requestAuthorizationWithAccount() method. It's the similar purpose with requestAuthorization(), but has optional accountName argument and returns authorized account name. The behaivor of requestAuthorization() is not changed from current version(may be...).
• Calling requestAuthorizationWithAccount() with no accountName, account selection dialog will be appeared or last signed in account will be used, as requestAuthorization().
• Else, calling requestAuthorizationWithAccount() with accountName, check the permission of specified account.
• When authorization was succeed, requestAuthorizationWithAccount() returns authroized account name("" will be returned on iOS) or null(authorization failed). I assume to the app will save the account name in sharedPreference, etc.
• Add optional accountName argument to getHealthDataFromTypes() (The argument will be simply ignored on iOS.). The plugin uses the specified account to access Google Fit data.

[matsunanaro]

Typo? Are you commenting out the write permission on purpose?

[masahiro-ikemoto]

In our project, only the fitness.*.read scope has applied for permission to access sensitive data and to remove the limit on the number of OAuth users.

Therefore, if we enable ACCESS_WRITE, it will be blocked by Google, so we comment it out to use with our app.

In general, I don't think there is a problem with enabling it, but it would be better if we could set whether to use the write function or not when we new HealthFactory.

[matsunanaro]

I'm afraid commenting out the line will have implication on all other users who need the write feature.
But I agree with you that there should be a possibility to opt out the write feature.

By the way, thanks for your quick response :-)

[masahiro-ikemoto]

I'm afraid commenting out the line will have implication on all other users who need the write feature.

Yes, I understand that, too.

I should have made the changes locally instead of pushing them to the repository, and I did it.

But I agree with you that there should be a possibility to opt out the write feature.

I hope you make it.

Thanks,

[matsunanaro]

Thanks for your latest commit.

And I've filed an enhancement issue #464