Add runtime dependency extraction for GN.

tools/gn/standard_out.cc

 // Copyright (c) 2013 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.
 
 #include "tools/gn/standard_out.h"
 
 #include <vector>
 
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 221 matching lines @@
       }
 
       // Highlight up to the colon (if any).
       size_t chars_to_highlight = line.find(':');
       if (chars_to_highlight == std::string::npos)
         chars_to_highlight = line.size();
 
       OutputString(line.substr(0, chars_to_highlight), DECORATION_YELLOW);
       OutputString(line.substr(chars_to_highlight) + "\n");
       continue;
-    } else if (!line.empty() && !in_body) {
+    } else if (is_markdown && !line.empty() && !in_body) {
       OutputString("```\n", DECORATION_NONE);
       in_body = true;
     }
 
     // Check for a comment.
     TextDecoration dec = DECORATION_NONE;
     for (const auto& elem : line) {
       if (elem == '#' && !is_markdown) {
         // Got a comment, draw dimmed.
         dec = DECORATION_DIM;
         break;
       } else if (elem != ' ') {
         break;
       }
     }
 
     OutputString(line + "\n", dec);
   }
 
   if (is_markdown && in_body)
     OutputString("\n```\n");
 }