Signal chrome_elf to initialize crash reporting, rather than doing it in DllMain

Currently, initialization crash reporting indirectly calls
CreateProcess() from chrome_elf's DllMain(), which causes deadlock in
some configurations (showing up in M54).

Instead, signal to chrome_elf that it should initialize crash reporting
later in WinMain(). This means we lose a little coverage that we were
hoping to gain from the move to chrome_elf, but a localized fix is
required for merge to stable.

Follow up bug is https://crbug.com/656800.

BUG=655788, 656800
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.win:win10_chromium_x64_rel_ng
TEST=enforce certificate rules per https://bugs.chromium.org/p/chromium/issues/detail?id=655788#c57 and then try to launch chrome.

Review-Url: https://codereview.chromium.org/2428703002
Cr-Commit-Position: refs/heads/master@{#425840}

chrome/app/chrome_exe_main_win.cc

@@ -204,6 +204,8 @@ int APIENTRY wWinMain(HINSTANCE instance, HINSTANCE prev, wchar_t*, int) {
 int main() {
   HINSTANCE instance = GetModuleHandle(nullptr);
 #endif
+  SignalInitializeCrashReporting();
+
   // Initialize the CommandLine singleton from the environment.
   base::CommandLine::Init(0, nullptr);
   const base::CommandLine* command_line =

chrome_elf/chrome_elf.def

@@ -7,6 +7,7 @@ LIBRARY  "chrome_elf.dll"
 EXPORTS
   IsBlacklistInitialized
   SignalChromeElf
+  SignalInitializeCrashReporting
   SuccessfullyBlocked
   GetBlacklistIndex
   AddDllToBlacklist

chrome_elf/chrome_elf_main.cc

@@ -11,17 +11,23 @@
 #include "chrome_elf/blacklist/blacklist.h"
 #include "chrome_elf/crash/crash_helper.h"
 
+// This function is a temporary workaround for https://crbug.com/655788. We
+// need to come up with a better way to initialize crash reporting that can
+// happen inside DllMain().
+void SignalInitializeCrashReporting() {
+  if (!elf_crash::InitializeCrashReporting()) {
+#ifdef _DEBUG
+    assert(false);
+#endif  // _DEBUG
+  }
+}
+
 void SignalChromeElf() {
   blacklist::ResetBeacon();
 }
 
 BOOL APIENTRY DllMain(HMODULE module, DWORD reason, LPVOID reserved) {
   if (reason == DLL_PROCESS_ATTACH) {
-    if (!elf_crash::InitializeCrashReporting()) {
-#ifdef _DEBUG
-      assert(false);
-#endif  // _DEBUG
-    }
 // CRT on initialization installs an exception filter which calls
 // TerminateProcess. We need to hook CRT's attempt to set an exception.
 // NOTE: Do not hook if ASan is present, or ASan will fail to install

chrome_elf/chrome_elf_main.h

@@ -5,6 +5,7 @@
 #ifndef CHROME_ELF_CHROME_ELF_MAIN_H_
 #define CHROME_ELF_CHROME_ELF_MAIN_H_
 
+extern "C" void SignalInitializeCrashReporting();
 extern "C" void SignalChromeElf();
 
 #endif  // CHROME_ELF_CHROME_ELF_MAIN_H_