Fixed/added namespace ending comments using clang-tidy. NFC

The patch is generated using this command:

  $ tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
      -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
      work/llvm/tools/clang

To reduce churn, not touching namespaces spanning less than 10 lines.

llvm-svn: 240270
diff --git a/clang/lib/CodeGen/CGBlocks.cpp b/clang/lib/CodeGen/CGBlocks.cpp
index 3fd344c..d3a3131 100644
--- a/clang/lib/CodeGen/CGBlocks.cpp
+++ b/clang/lib/CodeGen/CGBlocks.cpp
@@ -242,7 +242,7 @@
     
       return LeftValue > RightValue;
   }
-}
+} // namespace
 
 /// Determines if the given type is safe for constant capture in C++.
 static bool isSafeForCXXConstantCapture(QualType type) {
@@ -2249,7 +2249,7 @@
       CGF.BuildBlockRelease(Addr, BLOCK_FIELD_IS_BYREF);
     }
   };
-}
+} // namespace
 
 /// Enter a cleanup to destroy a __block variable.  Note that this
 /// cleanup should be a no-op if the variable hasn't left the stack