android: use the alt signal stack in child processes

Bug: 1113482, 1113065, crashpad:340
Change-Id: I2955a047e0e2dacba5db58913c163d1989cd4acc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2354463
Commit-Queue: Joshua Peraza <jperaza@chromium.org>
Commit-Queue: Mark Mentovai <mark@chromium.org>
Auto-Submit: Joshua Peraza <jperaza@chromium.org>
Reviewed-by: Mark Mentovai <mark@chromium.org>
Cr-Commit-Position: refs/heads/master@{#797877}

components/crash/core/app/crashpad_android.cc

@@ -156,7 +156,11 @@ class SandboxedHandler {
         strcmp(build_info->build_type(), "eng") == 0 ||
         strcmp(build_info->build_type(), "userdebug") == 0;
 
-    return Signals::InstallCrashHandlers(HandleCrash, 0, &old_actions_);
+    bool signal_stack_initialized =
+        CrashpadClient::InitializeSignalStackForThread();
+    DCHECK(signal_stack_initialized);
+    return Signals::InstallCrashHandlers(HandleCrash, SA_ONSTACK,
+                                         &old_actions_);
   }
 
   void HandleCrashNonFatal(int signo, siginfo_t* siginfo, void* context) {