inspector: remove AgentImpl

[eugeneo]

AgentImpl was introduce so inspector-agent.h does not leak libuv and
inspector implementation details. Inspector had been reworked since and
new classes provide this isolation and AgentImpl became unnecessary
level of indirection. This change removes that class to streamline the
code.

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• commit message follows commit guidelines

Affected core subsystem(s)

inspector - this is a pure refactoring change.

[bnoordhuis]

LGTM modulo comments.

[bnoordhuis]

static_cast?

[eugeneo]

Done.

[bnoordhuis]

Wouldn't ~Agent() = default; in the header file work?

[eugeneo]

No, the compiler is unable to instantiate ~unique_ptr at that point as it does not know if the classes have destructors.

[bnoordhuis]

I think I get it now, perhaps the comment is a little vague. The "incomplete types" refers to Agent's unique_ptr data members, not to a std::unique_ptr<Agent> instance elsewhere, correct?

Vague or not, it should at least be punctuated. :-)

[bnoordhuis]

Tiniest of nits: inconsistent parameter names (info vs. args.)

[eugeneo]

Fixed, also renamed in the cc file.

[bnoordhuis]

LGTM. You can drop the change to node.cc, should be fixed again in master.

[bnoordhuis]

I think I get it now, perhaps the comment is a little vague. The "incomplete types" refers to Agent's unique_ptr data members, not to a std::unique_ptr<Agent> instance elsewhere, correct?

Vague or not, it should at least be punctuated. :-)

[eugeneo]

CI: https://ci.nodejs.org/job/node-test-pull-request/7642/
Landed as: 439b35a

[bnoordhuis]

@eugeneo You missed this though:

it should at least be punctuated

[eugeneo]

@bnoordhuis I tried rewording the comment in another (unrelated) PR: https://github.com/nodejs/node/pull/12777/files#diff-8d16a44747475ef748bab83e5f9dade2R346