Improve public header file checking

tools/gn/header_checker.h

Index: tools/gn/header_checker.h
diff --git a/tools/gn/header_checker.h b/tools/gn/header_checker.h
index f1c7aa321a6daf5e52523ec05507797d1a1cfddb..f62ca2c818e0de3bb7c19b3ae0d385e9013a8475 100644
--- a/tools/gn/header_checker.h
+++ b/tools/gn/header_checker.h
@@ -18,7 +18,9 @@
 #include "tools/gn/err.h"
 
 class BuildSettings;
+class InputFile;
 class Label;
+class LocationRange;
 class SourceFile;
 class Target;
 
@@ -71,10 +73,13 @@ class HeaderChecker : public base::RefCountedThreadSafe<HeaderChecker> {
                  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