Improve GN public header file checking

tools/gn/header_checker.h

 // Copyright 2014 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.
 
 #ifndef TOOLS_GN_HEADER_CHECKER_H_
 #define TOOLS_GN_HEADER_CHECKER_H_
 
 #include <map>
 #include <set>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/run_loop.h"
 #include "base/strings/string_piece.h"
 #include "base/synchronization/lock.h"
 #include "tools/gn/err.h"
 
 class BuildSettings;
+class InputFile;
 class Label;
+class LocationRange;
 class SourceFile;
 class Target;
 
 namespace base {
 class MessageLoop;
 }
 
 class HeaderChecker : public base::RefCountedThreadSafe<HeaderChecker> {
  public:
   HeaderChecker(const BuildSettings* build_settings,
@@ skipping 32 matching lines @@
   // Resolves the contents of an include to a SourceFile.
   SourceFile SourceFileForInclude(const base::StringPiece& input) const;
 
   // from_target is the target the file was defined from. It will be used in
   // error messages.
   bool CheckFile(const Target* from_target,
                  const SourceFile& file,
                  Err* err) const;
 
   // Checks that the given file in the given target can include the given
-  // include file. If disallowed, returns false and sets the error.
+  // include file. If disallowed, returns false and sets the error. The
+  // range indicates the location of the include in the file for error
+  // reporting.
   bool CheckInclude(const Target* from_target,
-                    const SourceFile& source_file,
+                    const InputFile& source_file,
                     const SourceFile& include_file,
+                    const LocationRange& range,
                     Err* err) const;
 
   // Returns true if the given search_for target is a dependency of
   // search_from. Many subtrees are duplicated so this function avoids
   // duplicate checking across recursive calls by keeping track of checked
   // targets in the given set. It should point to an empty set for the first
   // call. A target is not considered to be a dependency of itself.
   bool IsDependencyOf(const Target* search_for,
                       const Target* search_from) const;
   bool IsDependencyOf(const Target* search_for,
@@ skipping 19 matching lines @@
   // These are mutable during runtime and require locking.
 
   base::Lock lock_;
 
   std::vector<Err> errors_;
 
   DISALLOW_COPY_AND_ASSIGN(HeaderChecker);
 };
 
 #endif  // TOOLS_GN_HEADER_CHECKER_H_