Rename class 'CFGReachabilityAnalysis' to 'CFGReverseBlockReachabilityAnalysis'.

This rename serves two purposes:

- It reflects the actual functionality of this analysis.
- We will have more than one reachability analysis.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@127930 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Checkers/IdempotentOperationChecker.cpp b/lib/StaticAnalyzer/Checkers/IdempotentOperationChecker.cpp
index b2177c9..8e4c673 100644
--- a/lib/StaticAnalyzer/Checkers/IdempotentOperationChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/IdempotentOperationChecker.cpp
@@ -531,7 +531,7 @@
                                                       const CFGBlock *CB,
                                                       const CoreEngine &CE) {
 
-  CFGReachabilityAnalysis *CRA = AC->getCFGReachablityAnalysis();
+  CFGReverseBlockReachabilityAnalysis *CRA = AC->getCFGReachablityAnalysis();
   
   // Test for reachability from any aborted blocks to this block
   typedef CoreEngine::BlocksAborted::const_iterator AbortedIterator;
@@ -556,10 +556,10 @@
   class VisitWL : public WorkList::Visitor {
     const CFGStmtMap *CBM;
     const CFGBlock *TargetBlock;
-    CFGReachabilityAnalysis &CRA;
+    CFGReverseBlockReachabilityAnalysis &CRA;
   public:
     VisitWL(const CFGStmtMap *cbm, const CFGBlock *targetBlock,
-            CFGReachabilityAnalysis &cra)
+            CFGReverseBlockReachabilityAnalysis &cra)
       : CBM(cbm), TargetBlock(targetBlock), CRA(cra) {}
     virtual bool visit(const WorkListUnit &U) {
       ProgramPoint P = U.getNode()->getLocation();