ios: Capture more exceptionReason in exception processor.
ios: Capture more exceptionReason in exception processor.

This brings Crashpad in line with what Breakpad captures.

Change-Id: I8ce2d81fc9cb150dc9817034fac3516f27f5661b
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/3611069
Reviewed-by: Joshua Peraza <f5809a5e35ec7e1bd0e25cb0a0b68bb433cf6f17@chromium.org>
Commit-Queue: Justin Cohen <45f934f548b3ee92957d72fd2179b802430e9402@chromium.org>

chromium/crashpad,chromium/crashpad,chromium/crashpad