Replace double-negated !SourceLocation.isInvalid() with SourceLocation.isValid().

llvm-svn: 249228
diff --git a/clang/lib/Analysis/ThreadSafety.cpp b/clang/lib/Analysis/ThreadSafety.cpp
index 922b157a..bce5175 100644
--- a/clang/lib/Analysis/ThreadSafety.cpp
+++ b/clang/lib/Analysis/ThreadSafety.cpp
@@ -787,7 +787,7 @@
       }
     }
 
-    if (!CurrBlockInfo->ExitLoc.isInvalid()) {
+    if (CurrBlockInfo->ExitLoc.isValid()) {
       // This block contains at least one statement. Find the source location
       // of the first statement in the block.
       for (CFGBlock::const_iterator BI = CurrBlock->begin(),