Re-enable pre-read experiment as a finch field trial.

chrome/common/chrome_constants.cc

 // Copyright (c) 2012 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/common/chrome_constants.h"
 
 #include "base/files/file_path.h"
 
 #define FPL FILE_PATH_LITERAL
 
@@ skipping 212 matching lines @@
 const int kJavaScriptMessageExpectedDelay = 1000;
 
 #if defined(OS_ANDROID)
 const bool kEnableTouchIcon = true;
 #else
 const bool kEnableTouchIcon = false;
 #endif
 
 const float kMaxShareOfExtensionProcesses = 0.30f;
 
+// This is used by the PreRead experiment.
+const char kPreReadEnvironmentVariable[] = "CHROME_PRE_READ_EXPERIMENT";
+
 #if defined(OS_LINUX)
 const int kLowestRendererOomScore = 300;
 const int kHighestRendererOomScore = 1000;
 #endif
 
 #if defined(OS_WIN)
-// This is used by the PreRead experiment.
-const char kPreReadEnvironmentVariable[] = "CHROME_PRE_READ_EXPERIMENT";
 // This is used by chrome in Windows 8 metro mode.
 const wchar_t kMetroChromeUserDataSubDir[] = L"Metro";
 const wchar_t kMetroNavigationAndSearchMessage[] =
     L"CHROME_METRO_NAV_SEARCH_REQUEST";
 const wchar_t kMetroGetCurrentTabInfoMessage[] =
     L"CHROME_METRO_GET_CURRENT_TAB_INFO";
 const wchar_t kMetroRegistryPath[] =
     L"Software\\" PRODUCT_STRING_PATH L"\\Metro";
 const wchar_t kLaunchModeValue[] = L"launch_mode";
 // This is used by breakpad and the metrics reporting.
 const wchar_t kBrowserCrashDumpAttemptsRegistryPath[] =
     L"Software\\" PRODUCT_STRING_PATH L"\\BrowserCrashDumpAttempts";
 #endif
 
 #if defined(OS_CHROMEOS)
 const char kProfileDirPrefix[] = "u-";
 #endif
 
 // This GUID is associated with any 'don't ask me again' settings that the
 // user can select for different file types.
 // {2676A9A2-D919-4FEE-9187-152100393AB2}
 const char kApplicationClientIDStringForAVScanning[] =
     "2676A9A2-D919-4FEE-9187-152100393AB2";
 
 }  // namespace chrome
 
 #undef FPL