Merge pull request #15032 from xedin/rdar-38203776

[AST] Disable comment printing while emitting diagnostics

Author: xedin

include/swift/AST/PrintOptions.h

@@ -402,6 +402,7 @@ struct PrintOptions {
     result.PrintIfConfig = false;
     result.ShouldQualifyNestedDeclarations =
         QualifyNestedDeclarations::TypesOnly;
+    result.PrintDocumentationComments = false;
     return result;
   }
 
@@ -418,6 +419,7 @@ struct PrintOptions {
     result.ElevateDocCommentFromConformance = true;
     result.ShouldQualifyNestedDeclarations =
         QualifyNestedDeclarations::Always;
+    result.PrintDocumentationComments = true;
     return result;
   }