Add 178663 back.

http://lab.llvm.org:8011/builders/clang-x86_64-darwin10-gdb went back green
before it processed the reverted 178663, so it could not have been the culprit.

Revert "Revert 178663."

This reverts commit 4f8a3eb2ce5d4ba422483439e20c8cbb4d953a41.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178682 91177308-0d34-0410-b5e6-96231b3b80d8
[analyzer] Fix typo.

Thanks Jordan!

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178683 91177308-0d34-0410-b5e6-96231b3b80d8
[analyzer] Properly handle the ternary operator in trackNullOrUndefValue

1) Look for the node where the condition expression is live when checking if
it is constrained to true or false.

2) Fix a bug in ProgramState::isNull, which was masking the problem. When
the expression is not a symbol (,which is the case when it is Unknown) return
unconstrained value, instead of value constrained to “false”!
(Thankfully other callers of isNull have not been effected by the bug.)

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178684 91177308-0d34-0410-b5e6-96231b3b80d8
[analyzer] make peelOffOuterExpr in BugReporterVisitors recursively peel off select Exprs

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178685 91177308-0d34-0410-b5e6-96231b3b80d8
[analyzer] Warn when nil receiver results in forming null reference

This also allows us to ensure IDC/return null suppression gets triggered in such cases.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178686 91177308-0d34-0410-b5e6-96231b3b80d8
[analyzer] Rename “Mac OS X API”, “Mac OS API” -> “API Misuse (Apple)”

As they are relevant on both Mac and iOS.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178687 91177308-0d34-0410-b5e6-96231b3b80d8