Print Preview: Add "print preview" back to about:flags; enable it by default just once.

chrome/browser/about_flags.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.
 
 #include "chrome/browser/about_flags.h"
 
 #include <algorithm>
 #include <iterator>
 #include <map>
 #include <set>
@@ skipping 157 matching lines @@
     kOsAll,
     SINGLE_VALUE_TYPE(switches::kDisableGpuVsync)
   },
   {
     "gpu-canvas-2d",  // FLAGS:RECORD_UMA
     IDS_FLAGS_ACCELERATED_CANVAS_2D_NAME,
     IDS_FLAGS_ACCELERATED_CANVAS_2D_DESCRIPTION,
     kOsWin | kOsLinux | kOsCrOS,
     SINGLE_VALUE_TYPE(switches::kEnableAccelerated2dCanvas)
   },
-#if !defined(GOOGLE_CHROME_BUILD) || defined(OS_MACOSX)
   // Only expose this for Chromium builds where users may not have the PDF
   // plugin. Do not give Google Chrome users the option to disable it here,
   // except on Mac, where it is disabled.
   {
     "print-preview",  // FLAGS:RECORD_UMA
     IDS_FLAGS_PRINT_PREVIEW_NAME,
     IDS_FLAGS_PRINT_PREVIEW_DESCRIPTION,
     kOsMac | kOsWin | kOsLinux,  // This switch is not available in CrOS.
     SINGLE_VALUE_TYPE(switches::kEnablePrintPreview)
   },
-#endif
   // TODO(dspringer): When NaCl is on by default, remove this flag entry.
   {
     switches::kEnableNaCl,  // FLAGS:RECORD_UMA
     IDS_FLAGS_ENABLE_NACL_NAME,
     IDS_FLAGS_ENABLE_NACL_DESCRIPTION,
     kOsAll,
     SINGLE_VALUE_TYPE(switches::kEnableNaCl)
   },
   {
     "dns-server",  // FLAGS:RECORD_UMA
@@ skipping 576 matching lines @@
 }
 
 const Experiment* GetExperiments(size_t* count) {
   *count = num_experiments;
   return experiments;
 }
 
 }  // namespace testing
 
 }  // namespace about_flags