[analyzer] Rename generateNode -> addTransition in CheckerContext

Also document addTransition methods.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@143059 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Checkers/ArrayBoundChecker.cpp b/lib/StaticAnalyzer/Checkers/ArrayBoundChecker.cpp
index f8cd335..a1a34f6 100644
--- a/lib/StaticAnalyzer/Checkers/ArrayBoundChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/ArrayBoundChecker.cpp
@@ -84,7 +84,7 @@
   
   // Array bound check succeeded.  From this point forward the array bound
   // should always succeed.
-  C.generateNode(StInBound);
+  C.addTransition(StInBound);
 }
 
 void ento::registerArrayBoundChecker(CheckerManager &mgr) {