Use implicit_cast<> instead of static_cast<> whenever possible

util/posix/symbolic_constants_posix.cc

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 95 matching lines @@
 
 const char kSigPrefix[] = "SIG";
 
 }  // namespace
 
 namespace crashpad {
 
 std::string SignalToString(int signal,
                            SymbolicConstantToStringOptions options) {
   const char* signal_name =
-      static_cast<size_t>(signal) < arraysize(kSignalNames)
+      implicit_cast<size_t>(signal) < arraysize(kSignalNames)
           ? kSignalNames[signal]
           : nullptr;
   if (!signal_name) {
     if (options & kUnknownIsNumeric) {
       return base::StringPrintf("%d", signal);
     }
     return std::string();
   }
 
   if (options & kUseShortName) {
     return std::string(signal_name);
   }
   return base::StringPrintf("%s%s", kSigPrefix, signal_name);
 }
 
 bool StringToSignal(const base::StringPiece& string,
                     StringToSymbolicConstantOptions options,
                     int* signal) {
   if ((options & kAllowFullName) || (options & kAllowShortName)) {
     bool can_match_full =
         (options & kAllowFullName) &&
         string.substr(0, strlen(kSigPrefix)).compare(kSigPrefix) == 0;
     base::StringPiece short_string =
         can_match_full ? string.substr(strlen(kSigPrefix)) : string;
     for (int index = 0;
-         index < static_cast<int>(arraysize(kSignalNames));
+         index < implicit_cast<int>(arraysize(kSignalNames));
          ++index) {
       const char* signal_name = kSignalNames[index];
       if (!signal_name) {
         continue;
       }
       if (can_match_full && short_string.compare(signal_name) == 0) {
         *signal = index;
         return true;
       }
       if ((options & kAllowShortName) && string.compare(signal_name) == 0) {
         *signal = index;
         return true;
       }
     }
   }
 
   if (options & kAllowNumber) {
     return StringToNumber(string, signal);
   }
 
   return false;
 }
 
 }  // namespace crashpad