Modify crash-reporter to collect crash information for unofficial builds.

The original code review link is here: http://codereview.chromium.org/6559003/

BUG=chromium-os:12207
TESTS=logging_UserCrash, logging_CrashSender, manual test which involves
purposely crashing a test to determine if minidump information is properly collected

Change-Id: I20274050cd698434951c65612e246f510c8082cb

TEST=

Review URL: http://codereview.chromium.org/6615021
diff --git a/crash_reporter/crash_collector.cc b/crash_reporter/crash_collector.cc
index 9600b44..5247d91 100644
--- a/crash_reporter/crash_collector.cc
+++ b/crash_reporter/crash_collector.cc
@@ -24,6 +24,7 @@
 static const char kShellPath[] = "/bin/sh";
 static const char kSystemCrashPath[] = "/var/spool/crash";
 static const char kUserCrashPath[] = "/home/chronos/user/crash";
+static const char kCrashTestInProgressPath[] = "/tmp/crash-test-in-progress";
 
 // Directory mode of the user crash spool directory.
 static const mode_t kUserCrashPathMode = 0755;
@@ -349,3 +350,7 @@
     LOG(ERROR) << "Unable to write " << meta_path.value();
   }
 }
+
+bool CrashCollector::IsCrashTestInProgress() {
+  return file_util::PathExists(FilePath(kCrashTestInProgressPath));
+}