Tweak |in_blink_namespace|, to look at ancestors *and also* at qualifiers.

tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // Changes Blink-style names to Chrome-style names. Currently transforms:
 //   fields:
 //     int m_operationCount => int operation_count_
 //   variables (including parameters):
 //     int mySuperVariable => int my_super_variable
 //   constants:
@@ skipping 48 matching lines @@
   return Node.isOverloadedOperator();
 }
 
 AST_MATCHER_P(clang::FunctionTemplateDecl,
               templatedDecl,
               clang::ast_matchers::internal::Matcher<clang::FunctionDecl>,
               InnerMatcher) {
   return InnerMatcher.matches(*Node.getTemplatedDecl(), Finder, Builder);
 }
 
+// If |InnerMatcher| matches |top|, then the returned matcher will match:
+// - |top::function|
+// - |top::Class::method|
+// - |top::internal::Class::method|
+AST_MATCHER_P(
+    clang::NestedNameSpecifier,
+    hasTopLevelPrefix,
+    clang::ast_matchers::internal::Matcher<clang::NestedNameSpecifier>,
+    InnerMatcher) {
+  const clang::NestedNameSpecifier* NodeToMatch = &Node;
+  while (NodeToMatch->getPrefix())
+    NodeToMatch = NodeToMatch->getPrefix();
+  return InnerMatcher.matches(*NodeToMatch, Finder, Builder);
+}
+
 // This will narrow CXXCtorInitializers down for both FieldDecls and
 // IndirectFieldDecls (ie. anonymous unions and such). In both cases
 // getAnyMember() will return a FieldDecl which we can match against.
 AST_MATCHER_P(clang::CXXCtorInitializer,
               forAnyField,
               clang::ast_matchers::internal::Matcher<clang::FieldDecl>,
               InnerMatcher) {
   const clang::FieldDecl* NodeAsDecl = Node.getAnyMember();
   return (NodeAsDecl != nullptr &&
           InnerMatcher.matches(*NodeAsDecl, Finder, Builder));
@@ skipping 505 matching lines @@
   llvm::InitializeNativeTargetAsmParser();
   llvm::cl::OptionCategory category(
       "rewrite_to_chrome_style: convert Blink style to Chrome style.");
   CommonOptionsParser options(argc, argv, category);
   clang::tooling::ClangTool tool(options.getCompilations(),
                                  options.getSourcePathList());
 
   MatchFinder match_finder;
   std::set<Replacement> replacements;
 
-  auto in_blink_namespace =
-      decl(hasAncestor(namespaceDecl(anyOf(hasName("blink"), hasName("WTF")),
-                                     hasParent(translationUnitDecl()))),
-           unless(isExpansionInFileMatching(kGeneratedFileRegex)));
+  // Blink namespace matchers ========
+  auto blink_namespace_decl =
+      namespaceDecl(anyOf(hasName("blink"), hasName("WTF")),
+                    hasParent(translationUnitDecl()));
+
+  // Given top-level compilation unit:
+  //   namespace WTF {
+  //     void foo() {}
+  //   }
+  // matches |foo|.
+  auto decl_under_blink_namespace = decl(hasAncestor(blink_namespace_decl));
+
+  // Given top-level compilation unit:
+  //   void WTF::function() {}
+  //   void WTF::Class::method() {}
+  // matches |WTF::function| and |WTF::Class::method| decls.
+  auto decl_has_qualifier_to_blink_namespace =
+      declaratorDecl(has(nestedNameSpecifier(
+          hasTopLevelPrefix(specifiesNamespace(blink_namespace_decl)))));
+
+  auto in_blink_namespace = decl(
+      anyOf(decl_under_blink_namespace, decl_has_qualifier_to_blink_namespace,
+            hasAncestor(decl_has_qualifier_to_blink_namespace)),
+      unless(isExpansionInFileMatching(kGeneratedFileRegex)));
 
   // Field, variable, and enum declarations ========
   // Given
   //   int x;
   //   struct S {
   //     int y;
   //     enum { VALUE };
   //   };
   // matches |x|, |y|, and |VALUE|.
   auto field_decl_matcher = id("decl", fieldDecl(in_blink_namespace));
@@ skipping 283 matching lines @@
   for (const auto& r : replacements) {
     std::string replacement_text = r.getReplacementText().str();
     std::replace(replacement_text.begin(), replacement_text.end(), '\n', '\0');
     llvm::outs() << "r:::" << r.getFilePath() << ":::" << r.getOffset()
                  << ":::" << r.getLength() << ":::" << replacement_text << "\n";
   }
   llvm::outs() << "==== END EDITS ====\n";
 
   return 0;
 }