Summary:
This is particularly important when using generated xcode project together with cocoapods (or anything that leverages a custom xcconfig)
If we do not set `$(inherited)`, then user will get cryptic "Symbol(s) not found for architecture ..." errors that will be really difficult to track down, especially for beginners. This happens because without setting `$(inherited)` we are essentially overriding settings provided on project level (rather than target level) as well as `.xcconfig` level.
**Test plan (required)**
```bash
react-native init MyProject
cd ios
pod init
```
Now go and add a pod to the `Podfile`, say
```ruby
pod 'HockeySDK'
```
And try to use it in `AppDelegate.m`
```objc
...
[[BITHockeyManager sharedHockeyManager] configureWithIdentifier:@"APP_IDENTIFIER"];
[[BITHockeyManager sharedHockeyManager] startManager];
```
Before this change, you'll get errors like this
![image](https://cloud.githubusercontent.com/assets/696842/15801450/feb3c036-2a4
Closes https://github.com/facebook/react-native/pull/7927
Differential Revision: D3430228
Pulled By: javache
fbshipit-source-id: ef453ad2e822726db0159d24ec93e301192e21de
Summary:The Obj-C tests were stalling when we updated TravisCI to use the OS X image with Xcode 7.3 and iOS 9.3.
On my own MBP with Xcode 7.3 the tests stall as well. Running `./scripts/objc-test.sh` prints out a warning near the end, which says `ld` couldn't find a Frameworks folder under the iPhoneSimulator9.3 SDK directory. Indeed, this directory doesn't exist on my computer. When creating a brand new project with unit tests and UI tests, both test targets don't specify "Framework Search Paths" so I don't think we need to specify it anymore.
Closes https://github.com/facebook/react-native/pull/7168
Differential Revision: D3216524
fb-gh-sync-id: 3097bda98d78289ecdba86801bcd461f3311ac47
fbshipit-source-id: 3097bda98d78289ecdba86801bcd461f3311ac47
Tony Xiao
Sean Kozer
James Ide
Alexey Lang
Alex Kotliarskyi
Pieter De Baets
Felix Oghină
