win: Fix multiple definition at link time for kSignature

client/crashpad_info.h

 // 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 75 matching lines @@
   //! disabled by SetCrashpadHandlerState(). Even when forwarding is enabled,
   //! the Crashpad handler may choose not to forward all exceptions to the
   //! system’s crash reporter in cases where it has reason to believe that the
   //! system’s crash reporter would not normally have handled the exception in
   //! Crashpad’s absence.
   void set_system_crash_reporter_forwarding(
       TriState system_crash_reporter_forwarding) {
     system_crash_reporter_forwarding_ = system_crash_reporter_forwarding;
   }
 
-  static const uint32_t kSignature = 'CPad';
+  enum : uint32_t {
+    kSignature = 'CPad',
+  };
 
  private:
   // The compiler won’t necessarily see anyone using these fields, but it
   // shouldn’t warn about that. These fields aren’t intended for use by the
   // process they’re found in, they’re supposed to be read by the crash
   // reporting process.
 #if defined(__clang__)
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wunused-private-field"
 #endif
@@ skipping 10 matching lines @@
 #if defined(__clang__)
 #pragma clang diagnostic pop
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(CrashpadInfo);
 };
 
 }  // namespace crashpad
 
 #endif  // CRASHPAD_CLIENT_CRASHPAD_INFO_H_