AU: Fall back to full updates after a number of failed delta update attempts.

prefs.cc

 // Copyright (c) 2010 The Chromium OS 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 "update_engine/prefs.h"
 
-#include "base/file_util.h"
-#include "base/logging.h"
-#include "base/string_number_conversions.h"
-#include "base/string_util.h"
+#include <base/file_util.h>
+#include <base/logging.h>
+#include <base/string_number_conversions.h>
+#include <base/string_util.h>
+
 #include "update_engine/utils.h"
 
 using std::string;
 
 namespace chromeos_update_engine {
 
+const char kPrefsDeltaUpdateFailures[] = "delta-update-failures";
 const char kPrefsLastActivePingDay[] = "last-active-ping-day";
 const char kPrefsLastRollCallPingDay[] = "last-roll-call-ping-day";
 
 bool Prefs::Init(const FilePath& prefs_dir) {
   prefs_dir_ = prefs_dir;
   return true;
 }
 
 bool Prefs::GetString(const string& key, string* value) {
   LOG(INFO) << "Getting key \"" << key << "\"";
@@ skipping 33 matching lines @@
   for (size_t i = 0; i < key.size(); ++i) {
     char c = key.at(i);
     TEST_AND_RETURN_FALSE(IsAsciiAlpha(c) || IsAsciiDigit(c) ||
                           c == '_' || c == '-');
   }
   *filename = prefs_dir_.Append(key);
   return true;
 }
 
 }  // namespace chromeos_update_engine