Switch the Clang plugin to use RecursiveASTVisitor.

tools/clang/plugins/FindBadConstructsConsumer.h

Index: tools/clang/plugins/FindBadConstructsConsumer.h
diff --git a/tools/clang/plugins/FindBadConstructsConsumer.h b/tools/clang/plugins/FindBadConstructsConsumer.h
index cf048ae8f573d13b56ce8684d920467cc6603080..6e2b2c9234265665bc47a0a2bcba1521518bc04d 100644
--- a/tools/clang/plugins/FindBadConstructsConsumer.h
+++ b/tools/clang/plugins/FindBadConstructsConsumer.h
@@ -21,6 +21,7 @@
 #include "clang/AST/ASTConsumer.h"
 #include "clang/AST/Attr.h"
 #include "clang/AST/CXXInheritance.h"
+#include "clang/AST/RecursiveASTVisitor.h"
 #include "clang/AST/TypeLoc.h"
 #include "clang/Basic/SourceManager.h"
 
@@ -30,11 +31,16 @@
 namespace chrome_checker {
 
 // Searches for constructs that we know we don't want in the Chromium code base.
-class FindBadConstructsConsumer : public ChromeClassTester {
+class FindBadConstructsConsumer
+    : public clang::RecursiveASTVisitor<FindBadConstructsConsumer>,
+      public ChromeClassTester {
  public:
   FindBadConstructsConsumer(clang::CompilerInstance& instance,
                             const Options& options);
 
+  // RecursiveASTVisitor:
+  bool VisitDecl(clang::Decl* decl);
+
   // ChromeClassTester overrides:
   void CheckChromeClass(clang::SourceLocation record_location,
                         clang::CXXRecordDecl* record) override;