Fix all relative includes to third_party.

samples/image_diff.cc

 // 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.
 
 // This file input format is based loosely on
 // Tools/DumpRenderTree/ImageDiff.m
 
 // The exact format of this tool's output to stdout is important, to match
 // what the run-webkit-tests script expects.
 
 #include <assert.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <string.h>
 
 #include <algorithm>
 #include <iostream>
 #include <map>
 #include <string>
 #include <vector>
 
-#include "../third_party/base/logging.h"
-#include "../third_party/base/numerics/safe_conversions.h"
 #include "image_diff_png.h"
+#include "third_party/base/logging.h"
+#include "third_party/base/numerics/safe_conversions.h"
 
 #if defined(OS_WIN)
 #include "windows.h"
 #endif
 
 // Return codes used by this utility.
 static const int kStatusSame = 0;
 static const int kStatusDifferent = 1;
 static const int kStatusError = 2;
 
@@ skipping 354 matching lines @@
     if (!diff_filename.empty()) {
       return DiffImages(filename1, filename2, diff_filename);
     }
   } else if (!filename2.empty()) {
     return CompareImages(filename1, filename2, histograms);
   }
 
   PrintHelp();
   return kStatusError;
 }