Trigger crash tests with IMMEDIATE_CRASH().

Use a well defined way to do this.

Change-Id: Ifb70fdc002251d00b8db73e8f8a6130c7a126357
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2227113Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#774340}

chrome/browser/chrome_browser_main.cc

@@ -314,8 +314,7 @@ base::RunLoop* g_run_loop = nullptr;
 void HandleTestParameters(const base::CommandLine& command_line) {
   // This parameter causes a null pointer crash (crash reporter trigger).
   if (command_line.HasSwitch(switches::kBrowserCrashTest)) {
-    int* bad_pointer = nullptr;
-    *bad_pointer = 0;
+    IMMEDIATE_CRASH();
   }
 }