Fix -Wwritable-strings warnings in kasko code.

chrome/chrome_watcher/system_load_estimator.cc

 // Copyright 2016 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/chrome_watcher/system_load_estimator.h"
 
 #include <vector>
 
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/threading/platform_thread.h"
 
 namespace chrome_watcher {
 namespace {
 
 using CounterHandle = SystemLoadEstimator::CounterHandle;
 
 uint64_t FileTimeToUInt64(FILETIME time) {
   ULARGE_INTEGER output = {};
   output.LowPart = time.dwLowDateTime;
   output.HighPart = time.dwHighDateTime;
   return static_cast<uint64_t>(output.QuadPart);
 }
 
 CounterHandle AddPdhCounter(PDH_HQUERY query,
-                            wchar_t* object_name,
-                            wchar_t* counter_name) {
+                            const wchar_t* object_name,
+                            const wchar_t* counter_name) {
   DCHECK(counter_name);
 
   // Get the counter's path.
   PDH_COUNTER_PATH_ELEMENTS path_elements = {
-      nullptr, object_name, nullptr, nullptr, 0, counter_name};
+      nullptr, const_cast<LPTSTR>(object_name), nullptr, nullptr,
+      0,       const_cast<LPTSTR>(counter_name)};
   std::unique_ptr<wchar_t[]> counter_path(new wchar_t[PDH_MAX_COUNTER_PATH]);
   DWORD path_len = PDH_MAX_COUNTER_PATH;
 
   PDH_STATUS status =
       ::PdhMakeCounterPath(&path_elements, counter_path.get(), &path_len, 0);
   if (status != ERROR_SUCCESS)
     return CounterHandle();
 
   // Add the counter.
   HCOUNTER counter_raw = nullptr;
@@ skipping 124 matching lines @@
   if (!::GetSystemTimes(&time_idle, &time_kernel, &time_user))
     return false;
 
   // Note: kernel time includes idle time.
   *idle = FileTimeToUInt64(time_idle);
   *total = FileTimeToUInt64(time_kernel) + FileTimeToUInt64(time_user);
   return true;
 }
 
 }  // namespace chrome_watcher