Fix issue causing blank white dialog when loading friends list

Summary:
Set the UIActivityIndicator color to gray to stop it from blending into the background.
On iOS5 we do this by setting the color to gray. On older iOS versions which don't support this
property, this is done by setting the style to UIActivityIndicatorViewStyleGray instead of
UIActivityIndicatorViewStyleWhiteLarge which results in a slightly smaller indicator.

Test Plan: Testing using Hackbook.

Reviewers: jacl, dgibson

Reviewed By: jacl

Differential Revision: https://phabricator.fb.com/D426894

Task ID: 908016
Use [NSDictionary objectForKey:] instead of [NSDictionary valueForKey:] to access objects in dictionaries

Summary: valueForKey also works in this case since none of our keys are strings staring with "@". However, objectForKey: is the correct selector to use for the desired behavior.

Test Plan: Verify behavior with HackBook app

Reviewers: jacl, dgibson

Reviewed By: jacl

Differential Revision: https://phabricator.fb.com/D427850

Task ID: 854847
Fix a bug that caused request: didLoad: to be called with the raw response instead of a string when the response does not represent a valid JSON object.

Summary:
If the response is not a JSON object, convert the actual response to a string instead of using the NSData object.
This will break clients that depend on the current behavior. If you need access to the raw response, use request: diReceiveResponse: instead.

Test Plan: Test with stream.publish requests

Reviewers: jacl, dgibson, yariv, caabernathy

Reviewed By: jacl

CC: leon

Differential Revision: https://phabricator.fb.com/D427844

Task ID: 842334
Fix memory leaks in Hackbook

Summary:
1) img was alloc'ed and never released while uploading a photo
2) alertview was alloc'ed and never released
3) friendswithapp was alloc'ed twice and never released, updated the logic to use obj c syntax
4) UIGraphicsGetImageFromCurrentImageContext() returns an autoreleased imageView - retaining it is the incorrect solution. See http://stackoverflow.com/questions/1529667/memory-allocation-and-release-for-uiimage-in-iphone

Test Plan:
Run Hackbook in the profiler and verify no memory leaks when loading userpic from the graph api
Upload a photo, verify no longer leaks
View friends with app, verify no longer leaks
Pop the alertview and verify no longer leaks

Reviewers: jacl, caabernathy, mattwkelly, selekman

Reviewed By: jacl

Differential Revision: https://phabricator.fb.com/D430905

Task ID: 980129
Fix Xcode build path in the static lib build script for Xcode 4.3.1+ or version downloaded from App Store

Summary: Previously xcodebuild could be found under the /Developer directory but it has since moved for Xcode downloaded from the App Store. If the developer has migrated from one version to another, then calling "which xcodebuild" will not work, unless they have run a script called "xcode-select switch". So for now we first check the older location, then look in the newer App Store location.

Test Plan: I tried running the build script in my folder after a recent upgrade from 4.2 to 4.3.1. Without the build script change I got an error. With the build script change, the library was generated.

Reviewers: mmarucheck, bruce, jacl

Reviewed By: jacl

CC: selekman, vijaye, jacl, gregschechte

Differential Revision: https://phabricator.fb.com/D440943

Revert Plan: OK

Task ID: 998703
Rolling up a few pull requests -- thanks!

Summary:
This diff rolls-up the following pull request -
  * 449      - SevaUA
  * 446, 445 - adamvduke
  * 435      - deyton

Test Plan: manual, used hackbook to exercise impacted code

Reviewers: yariv, mmarucheck, vijaye, caabernathy

Reviewed By: vijaye

CC: gregschechte, selekman

Differential Revision: https://phabricator.fb.com/D448786

Task ID: 1021338, 981999
Fixes a recursion bug introduced in the previous diff

Summary:
Reverting the portion of the previous diff that attempted to reuse a reference as a bool,
given that the reference is assigned to late to be used to short-circuit recursion
Fixes string comparison defect

Summary: summary says it all

Test Plan: a little white-box testing with hackbook

Reviewers: mmarucheck, caabernathy, yariv

Reviewed By: mmarucheck

Differential Revision: https://phabricator.fb.com/D457449
merged in changes from upstream/master