Merge Crashpad to the 42.0.2311 branch

Merge Crashpad to the 42.0.2311 branch.

The description from the original trunk commit to integrate Crashpad
(https://codereview.chromium.org/1001103002, d413b2dcb549) was:

> 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.
>
> This also includes follow-ups made after the original landing, tracked
> under https://crbug.com/466964.

This cherry-picks the following changes:

9470f6bca0fe Add additional move support to ScopedGeneric in the form of
             operator=
d413b2dcb549 Crashpad!: Use the Crashpad client instead of Breakpad on
             Mac OS X
18fcae1dee18 Fix sign_versioned_dir.sh.in
ffda27708784 Update Crashpad to e7b80a52f5b9832814485b58f66d4b13117a5186
d93ac0ad1929 Update Crashpad to 1d022a86db566613c11ff03ad6e791f9c01ffe88
4dc0534fabb2 Update Crashpad to 82bebb11de699550a36bf411737d01880e4a16a7
9f2fdc07d83f Update Crashpad to 5d0a133ecd6625f30c6491d502f12f26a0bef32d
8e57e5ba56c3 Don't show "requires Chrome restart" when toggling stats
             reporting preference on Mac OS X
c67fa64ff085 Set a "metrics_client_id" crash key instead of "guid" on
             Mac OS X

Crashpad changes included in "update Crashpad" commits include:

6bf80c3e4859 Add MinidumpCrashpadInfo::report_id
e7b80a52f5b9 win: Add UUID::InitializeFromSystemUUID()
1d022a86db56 handler/mac: Support the in-Chromium
             component=shared_library configuration
98cca0e5fcb4 compat/mac: SDK compatibility for pre-Xcode 4.2 10.6 SDK
82bebb11de69 Update man pages
d516689641d8 Update crashpad.doxy to Doxygen 1.8.9.1
1e12b471e376 Update mini_chromium to 6c49a5924dea
c2502f45c9b2 doc: Add documentation-generating scripts to the Crashpad
             tree
c052c97c7e2c Update crashpad_handler man page to document all options
af9e78940e8c Allow man pages to link to each other
4bd97bb6db2a Document CrashpadInfo::set_simple_annotations()
6f4e6aacc885 Add crashpad_database_util and its man page
7fa250c9a238 Roll mini_chromium to 2f02dcc73536
8b4932e56034 Update mini_chromium to 31e989ac0b03
79ae055e50b1 Add Locking calls to file_io.h plus implementations and
             test
71deedee44d0 doxygen: Prevent the word Thread with a capital T from
             automatically linking to test::Thread.
0c704745dd65 Followup to https://codereview.chromium.org/1001673002/
5d0a133ecd66 Tolerate weird cl_kernels modules

TBR=amineer@chromium.org, rsesek@chromium.org
BUG=386208, 390217, 415547, 427611, 466964, crashpad:12
Committed: https://chromium.googlesource.com/chromium/src/+/1fd9385ae419d92b1b4bf4001b1c319625fe6df5

[Mark Mentovai, 2015-03-24 20:32:59]

mark@chromium.org changed reviewers:
+ amineer@chromium.org, rsesek@chromium.org

[Mark Mentovai, 2015-03-24 21:09:42]

Committed patchset #1 (id:1) manually as
1fd9385ae419d92b1b4bf4001b1c319625fe6df5 (presubmit successful).