Minor improvements to GN's "desc" output.

tools/gn/visibility.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_VISIBILITY_H_
 #define TOOLS_GN_VISIBILITY_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 50 matching lines @@
   // Sets the visibility to be public.
   void SetPublic();
 
   // Sets the visibility to be private to the given directory.
   void SetPrivate(const SourceDir& current_dir);
 
   // Returns true if the target with the given label can depend on one with the
   // current visibility.
   bool CanSeeMe(const Label& label) const;
 
-  // Returns a string listing the visibility.
-  std::string Describe() const;
+  // Returns a string listing the visibility. |indent| number of spaces will
+  // be added on the left side of the output. If |include_brackets| is set, the
+  // result will be wrapped in "[ ]" and the contents further indented. The
+  // result will end in a newline.
+  std::string Describe(int indent, bool include_brackets) const;
 
   // Converts the given input string to a pattern. This does special stuff
   // to treat the pattern as a label. Sets the error on failure.
   static VisPattern GetPattern(const SourceDir& current_dir,
                                const Value& value,
                                Err* err);
 
   // Helper function to check visibility between the given two items. If
   // to is invisible to from, returns false and sets the error.
   static bool CheckItemVisibility(const Item* from, const Item* to, Err* err);
 
   // Helper function to fill an item's visibility from the "visibility" value
   // in the current scope.
   static bool FillItemVisibility(Item* item, Scope* scope, Err* err);
 
  private:
   std::vector<VisPattern> patterns_;
 
   DISALLOW_COPY_AND_ASSIGN(Visibility);
 };
 
 #endif  // TOOLS_GN_VISIBILITY_H_