Add small troubleshooting for importing sample app

[leonjoosse]

I would like to clarify this issue in the README: #1349

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[leonjoosse]

I signed it!

[googlebot]

CLAs look good, thanks!

[samtstern]

@leonjoosse thanks for this clarification! LGTM, @SUPERCILEX wdyt?

[SUPERCILEX]

@samtstern This is kinda Studio's fault, but I don't see why not. 😃

[trigal2012]

I'm new to Android and Firebase and I'm trying to use this project. I clone the entire project locally, then opened AS, selected import, then I chose "import project from external model", clicked on Next. The form is then looking for the "Gradle Home". "Use local gradle distribution" is selected. What value do I enter here? I've tried pointing it to the "gradle" folder located at "FirebaseUI-android/gradle" but that did not work. I also tried pointing to "FirebaseUI-android/app". I also removed the .idea folder. any help is appreciated.

[SUPERCILEX]

@trigal2012 Yeah, that dialog is annoying. Just select the first option to use the Gradle wrapper and click next. I think AS 3.2 will be able to handle the project better.

[trigal2012]

@SUPERCILEX thanks for the quick response. looks like I may have another issue because the option you mentioned is grayed out. I'll dig around. Thanks!