style plugin: Don't ignore style warnings on the linux clang trybots.

tools/clang/plugins/ChromeClassTester.cpp

 // Copyright (c) 2011 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.
 
 // A general interface for filtering and only acting on classes in Chromium C++
 // code.
 
 #include "ChromeClassTester.h"
 
 #include <sys/param.h>
@@ skipping 36 matching lines @@
   banned_directories_.push_back("testing/");
   banned_directories_.push_back("googleurl/");
   banned_directories_.push_back("v8/");
   banned_directories_.push_back("sdch/");
 
   // Don't check autogenerated headers.
   banned_directories_.push_back("out/");
   banned_directories_.push_back("llvm/");
   banned_directories_.push_back("ninja/");
   banned_directories_.push_back("xcodebuild/");
-  banned_directories_.push_back("clang/");
 
   // You are standing in a mazy of twisty dependencies, all resolved by
   // putting everything in the header.
   banned_directories_.push_back("automation/");
 
   // Don't check system headers.
   banned_directories_.push_back("/Developer/");
 
   // Used in really low level threading code that probably shouldn't be out of
   // lined.
@@ skipping 158 matching lines @@
     char resolvedPath[MAXPATHLEN];
     if (realpath(b.c_str(), resolvedPath)) {
       b = resolvedPath;
     }
 
     for (std::vector<std::string>::const_iterator it =
              banned_directories_.begin();
          it != banned_directories_.end(); ++it) {
       // If we can find any of the banned path components in this path, then
       // this file is rejected.
-      if (b.find(*it) != std::string::npos)
-        return true;
+      size_t index = b.find(*it);
+      if (index != std::string::npos) {
+        bool matches_full_dir_name = index == 0 || b[index - 1] == '/';
+        if ((*it)[0] == '/')
+          matches_full_dir_name = true;
+        if (matches_full_dir_name)
+          return true;
+      }
     }
   }
 
   return false;
 }
 
 bool ChromeClassTester::IsIgnoredType(const std::string& base_name) {
   return ignored_record_names_.find(base_name) != ignored_record_names_.end();
 }