[android] Fix SIGABRT handling in the WebView crash handler.
The WebView fingerprint crash handler introduced in crrev.com/
678763005
was failing to cover the case of signals delivered through kill/raise.
Conversely to what happens with segfaults, where the kernel keeps
invoking the registered SIGSEGV handler, in these other cases the signal
needs to be re-enqueued before chaining to the next handler.
This is the case of abort(), which internally does a raise(SIGABRT).
BUG=437788
Review URL: https://codereview.chromium.org/
769843002
Cr-Commit-Position: refs/heads/master@{#306179}