Summary:Hey,
I have been going through some UIAlert related issues in the repo trying to fix them, and one of the steps to start reproducing them was to put `Alert.alert()` call right inside `componentDidMount`.
However, I've started noticing strange bugs as long as I didn't set 1second timeout.
Started digging in deeper, and I've noticed the `UIAlert` gets attached to the `RCTWindow()` mainViewController.
However - since RCTDevLoadingView adds a `keyWindow`, that is the window that will be returned at the time of the call and the window `UIAlert` will be attached to.
To visualise that better - you can take a look at these two frames when app is being loaded:
<img width="371" alt="screen shot 2016-04-20 at 22 02 45" src="https://cloud.githubusercontent.com/assets/2464966/14688596/ae8d292c-0743-11e6-8aeb-e45da391b5b5.png">
<img width="371" alt="screen shot 2016-04-20 at 22 02 58" src="https://cloud.githubusercontent.com/assets/2464966/14688599/b30798e8-0743-11e6-951a-463fe7324c56.png">
AFAIK we do
Closes https://github.com/facebook/react-native/pull/7098
Differential Revision: D3207395
Pulled By: javache
fb-gh-sync-id: f8dca063573ac6f2a0ec497138b2ed0a7b27788b
fbshipit-source-id: f8dca063573ac6f2a0ec497138b2ed0a7b27788b
0de8962e16
