[cloud_functions]fixed error introduced by #1210

[rishabnayak]

Fixes flutter/flutter#28578, which was an artifact introduced by #1210 which tried to fix flutter/flutter#27888 and flutter/flutter#24333.

This issue is most likely caused by #1210 as this commit is correlated with the version roll to 0.1.1, which is confirmed by git blame.

Thanks to @aytunch for confirming that the build works with cloud_functions: 0.1.0+1

Performs a null check on the variable, reverting it to the default us-central1 if not found.

[cyanglaz]

I feel like defaulting to a certain value behind the scene might be hard to debug for users that does not enable the "us-central1" region in their application. Do google cloud always enable "us-central1"?
Maybe `assert (region != null) is better.
@collinjackson

[rishabnayak]

I agree, but apparently the Cloud Functions docs say that they run in the us-central1 region by default. Here's the link

[collinjackson]

Thanks for the contribution! I fixed this a different way, see #1316

[gustavobrian]

help me please:
firebase_auth: ^0.8.1+4
cloud_firestore: ^0.9.5+2
cloud_functions: 0.1.1+1
firebase_storage: ^2.1.0+1
firebase_core: ^0.3.1+1
firebase_analytics: ^2.0.3
firebase_messaging: ^4.0.0+1

Xcode's output:
↳
/Volumes/Home/gustavobrian/.pub-cache/hosted/pub.dartlang.org/cloud_functions-0.1.1+1/ios/Classes/CloudFunctionsPlugin.m:49:16: error: no visible @interface for 'FIRFunctions' declares the selector 'callFunction:withObject:completion:'
[functions callFunction:functionName
~~~~~~~~~ ^~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.

[rishabnayak]

@gustavobrian #1316 fixed this issue, there should be a version bump for cloud_functions from 0.1.1+1 to 0.1.2 soon; that should take care of this issue for you! Till then, hold on, or, you could get the bleeding-edge version by editing your cloud_functions entry in your pubspec.yaml file to look like this

  cloud_functions:
    git:
      url: https://github.com/flutter/plugins.git
      path: packages/cloud_functions

[gustavobrian]

#1316

i love you!!!