[analyzer] Look through all casts when trying to track constraints.

Previously, we were losing path notes (in both text and plist form)
because the interesting DeclRefExpr was buried in a cast.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@161999 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp b/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
index 46aa9e2..e729587 100644
--- a/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
+++ b/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
@@ -323,7 +323,7 @@
   // Walk through lvalue-to-rvalue conversions.
   const Expr *Ex = dyn_cast<Expr>(S);
   if (Ex) {
-    Ex = Ex->IgnoreParenLValueCasts();
+    Ex = Ex->IgnoreParenCasts();
     if (const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(Ex)) {
       if (const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl())) {
         const VarRegion *R =