Crashpad!: Use the Crashpad client instead of Breakpad on Mac OS X.

Crashpad is always compiled in to Chrome and its handler is always
enabled. It is only possible to enable uploads in official builds.

Crashpad talks to the existing Breakpad server. There should be no
noticeable changes to crash reporting on the server side, except the
client IDs will all change to a new ID and will no longer be
synchronized with UMA client IDs. This is a one-time change. After this,
the client ID will remain stable within a single --user-data-dir.


Review URL:

Cr-Commit-Position: refs/heads/master@{#320466}
33 files changed