Update clang to r339409.

Change-Id: I800772d2d838223be1f6b40d490c4591b937fca2
diff --git a/linux-x64/clang/include/llvm/Support/YAMLTraits.h b/linux-x64/clang/include/llvm/Support/YAMLTraits.h
index b874ad5..4b8c4e9 100644
--- a/linux-x64/clang/include/llvm/Support/YAMLTraits.h
+++ b/linux-x64/clang/include/llvm/Support/YAMLTraits.h
@@ -540,11 +540,14 @@
     case '.':
     case ',':
     case ' ':
-    // TAB (0x9), LF (0xA), CR (0xD) and NEL (0x85) are allowed.
+    // TAB (0x9) is allowed in unquoted strings.
     case 0x9:
+      continue;
+    // LF(0xA) and CR(0xD) may delimit values and so require at least single
+    // quotes.
     case 0xA:
     case 0xD:
-    case 0x85:
+      MaxQuotingNeeded = QuotingType::Single;
       continue;
     // DEL (0x7F) are excluded from the allowed character range.
     case 0x7F:
@@ -1311,7 +1314,7 @@
   Output(raw_ostream &, void *Ctxt = nullptr, int WrapColumn = 70);
   ~Output() override;
 
-  /// \brief Set whether or not to output optional values which are equal
+  /// Set whether or not to output optional values which are equal
   /// to the default value.  By default, when outputting if you attempt
   /// to write a value that is equal to the default, the value gets ignored.
   /// Sometimes, it is useful to be able to see these in the resulting YAML