[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/ArrayBoundCheckerV2.cpp b/lib/StaticAnalyzer/Checkers/ArrayBoundCheckerV2.cpp
index 6175028..5973356 100644
--- a/lib/StaticAnalyzer/Checkers/ArrayBoundCheckerV2.cpp
+++ b/lib/StaticAnalyzer/Checkers/ArrayBoundCheckerV2.cpp
@@ -166,7 +166,7 @@
   while (false);
   
   if (state != originalState)
-    checkerContext.generateNode(state);
+    checkerContext.addTransition(state);
 }
 
 void ArrayBoundCheckerV2::reportOOB(CheckerContext &checkerContext,