Implement Dump-on-DCHECK (via a new LogSeverity).

base/debug/dump_without_crashing.h

 // Copyright 2013 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.
 
 #ifndef BASE_DEBUG_DUMP_WITHOUT_CRASHING_H_
 #define BASE_DEBUG_DUMP_WITHOUT_CRASHING_H_
 
 #include "base/base_export.h"
 #include "base/compiler_specific.h"
 #include "build/build_config.h"
 
 namespace base {
 
 namespace debug {
 
 // Handler to silently dump the current process without crashing.
 // Before calling this function, call SetDumpWithoutCrashingFunction to pass a
 // function pointer, typically chrome!DumpProcessWithoutCrash.  See example code
 // in chrome_main.cc that does this for chrome.dll.
-BASE_EXPORT void DumpWithoutCrashing();
+// Returns false if called before SetDumpWithoutCrashingFunction.
+BASE_EXPORT bool DumpWithoutCrashing();

[Wez, 2016/12/19 23:57:46]

Some new call-sites have been introduced lately which Bind() this, assuming it
returns void.

Q: Would it be cleaner to add an explicit Dump1stTimeWithoutCrashing()?

Q: To ensure test reliability, should we also have ResetDump1stTimeForTest()?

 
 // Sets a function that'll be invoked to dump the current process when
 // DumpWithoutCrashing() is called.
 BASE_EXPORT void SetDumpWithoutCrashingFunction(void (CDECL *function)());
 
 }  // namespace debug
 
 }  // namespace base
 
 #endif  // BASE_DEBUG_DUMP_WITHOUT_CRASHING_H_