Add support for multiple browser instances reliability tests.

chrome/tools/crash_service/crash_service.h

Index: chrome/tools/crash_service/crash_service.h
===================================================================
--- chrome/tools/crash_service/crash_service.h	(revision 150982)
+++ chrome/tools/crash_service/crash_service.h	(working copy)
@@ -62,6 +62,9 @@
   // Override the name of the Windows named pipe on which we will
   // listen for crash dump request messages.
   static const char kPipeName[];
+  // --archive-dumps-by-pid
+  // Archive crash dumps into separate directory by client process id.
+  static const char kArchiveDumpsByPid[];
 
   // Returns number of crash dumps handled.
   int requests_handled() const {
@@ -102,6 +105,9 @@
   // LocalFree.
   PSECURITY_DESCRIPTOR GetSecurityDescriptorForLowIntegrity();
 
+  // Whether to archive crash dumps by client process id.
+  static bool archive_dumps_by_pid_;
+
   google_breakpad::CrashGenerationServer* dumper_;
   google_breakpad::CrashReportSender* sender_;