Change DumpProcessWithoutCrash to use load-time dynamic linking

chrome_elf/chrome_elf_main.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 CHROME_ELF_CHROME_ELF_MAIN_H_
 #define CHROME_ELF_CHROME_ELF_MAIN_H_
 
 extern "C" void SignalInitializeCrashReporting();
 extern "C" void SignalChromeElf();
+extern "C" void DumpWithoutCrashing();

[robertshield, 2017/06/22 18:15:40]

When included in chrome_main.cc, is this extern resolved to the implementation
from components/crash/content/app/crashpad_win.cc? If so, should chrome_main.cc
#include components/crash/content/app/crashpad.h instead?

[Will Harris, 2017/06/26 12:26:20]

no, because that's namespaced crash_reporter::DumpWithoutCrashing.

I re-verified in a debug build that the calls work fine when calling
dumpwithoutcrashing - they go from

base -> chrome_elf!DumpWithoutCrashing -> 
chrome_elf!elf_crash::DumpWithoutCrashing -> 
chrome_elf!crash_reporter::DumpWithoutCrashing -> 
chrome_elf!crashpad::CrashpadClient::DumpWithoutCrash

as expected. This works from both chrome.exe and chrome.dll/chrome_child.dll

See https://pastebin.com/raw/sGaDsU2Q

[robertshield, 2017/06/27 14:47:17]

Hrmm. Ok, I see, I didn't notice the crash_reporter namespace when first
reading.

That's a little confusing and I'd suggest either renaming one of the
DumpWithoutCrashing functions or adding comments in chrome_main.cc at the 

base::debug::SetDumpWithoutCrashingFunction(&DumpWithoutCrashing);

line indicating that this is taking the function from chrome_elf since future
hapless code searchers like myself may get confused by this. 

[Will Harris, 2017/06/27 16:13:27]

Done.

 
 #endif  // CHROME_ELF_CHROME_ELF_MAIN_H_