Merge pull request #8234 from practicalswift/use-isa-instead-of-dyn_cast-if-the-result-is-not-needed

[gardening] Use isa<T> instead of dyn_cast<T> if the result is not needed

Author: practicalswift

tools/SourceKit/lib/SwiftLang/SwiftDocSupport.cpp

@@ -161,7 +161,7 @@ class AnnotatingPrinter : public StreamPrinter {
 
   bool shouldContinuePost(const Decl *D, Optional<BracketOptions> Bracket) {
     assert(Bracket.hasValue());
-    if (!Bracket.getValue().shouldCloseNominal(D) && dyn_cast<NominalTypeDecl>(D))
+    if (!Bracket.getValue().shouldCloseNominal(D) && isa<NominalTypeDecl>(D))
       return false;
     if (!Bracket.getValue().shouldCloseExtension(D) &&
         isa<ExtensionDecl>(D))