Remove PRODUCT_STRING_PATH from chrome_constants.h on Windows.

components/browser_watcher/exit_code_watcher_win.cc

 // Copyright (c) 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.
 
 #include "components/browser_watcher/exit_code_watcher_win.h"
 
 #include <utility>
 
 #include "base/logging.h"
 #include "base/process/kill.h"
 #include "base/strings/stringprintf.h"
 #include "base/win/registry.h"
 
 namespace browser_watcher {
 
 namespace {
 
 base::string16 GetValueName(const base::Time creation_time,
                             base::ProcessId pid) {
   // Convert the PID and creation time to a string value unique to this
   // process instance.
   return base::StringPrintf(L"%d-%lld", pid, creation_time.ToInternalValue());
 }
 
 }  // namespace
 
-ExitCodeWatcher::ExitCodeWatcher(const base::char16* registry_path) :
-    registry_path_(registry_path), exit_code_(STILL_ACTIVE) {
-}
+ExitCodeWatcher::ExitCodeWatcher(base::StringPiece16 registry_path)
+    : registry_path_(registry_path.as_string()), exit_code_(STILL_ACTIVE) {}
 
 ExitCodeWatcher::~ExitCodeWatcher() {
 }
 
 bool ExitCodeWatcher::Initialize(base::Process process) {
   if (!process.IsValid()) {
     LOG(ERROR) << "Invalid parent handle, can't get parent process ID.";
     return false;
   }
 
@@ skipping 40 matching lines @@
   ULONG result = key.WriteValue(value_name.c_str(), exit_code);
   if (result != ERROR_SUCCESS) {
     LOG(ERROR) << "Unable to write to registry, error " << result;
     return false;
   }
 
   return true;
 }
 
 }  // namespace browser_watcher