[analyzer] Add getLocationContext to CheckerContext

CheckerContext::getPredecessor is only used to get to the LocationContext
half of the times.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@143061 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp b/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp
index 9d5660c..0d3059e 100644
--- a/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp
@@ -150,7 +150,7 @@
 
     CallBack(CheckerContext &CC) :
       Ctx(CC),
-      CurSFC(CC.getPredecessor()->getLocationContext()->getCurrentStackFrame())
+      CurSFC(CC.getLocationContext()->getCurrentStackFrame())
     {}
     
     bool HandleBinding(StoreManager &SMgr, Store store,