GitLab

Adds DumpWithoutCrashingForClient() which enables generating a dump on
behalf of the embedding app (represented by AwDebugCrashReporterClient)

This also includes refactoring of native code in minidump_uploader
to expose MimeifyReport() and WriteBodyToFile(), to be used by
AwDebug::DumpWithoutCrashing() in the followup CL.

Change-Id: If528bf060b6acaa51d0facaf1f1adf784c1852e6
Reviewed-on: https://chromium-review.googlesource.com/c/1269099
Commit-Queue: Joshua Peraza <jperaza@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Tobias Sargeant <tobiasjs@chromium.org>
Reviewed-by: Mark Mentovai <mark@chromium.org>
Cr-Commit-Position: refs/heads/master@{#612955}