[TIMOB-15192]iOS: Possible fix for splash screen flickering issue on iOS 7

__Test Instruction__ 

Import the following [app](https://dl.dropboxusercontent.com/u/43336767/splashtest%202.zip) to TiStudio.
build and install the app to device. 
Start the app in different orientation make sure the correct Splash screen is loaded and no flicker is observed.