src: fewer uses of NODE_USE_V8_PLATFORM

[codebytere]

This PR removes some uses of NODE_USE_V8_PLATFORM in conjunction with HAVE_INSPECTOR.

Electron makes use of HAVE_INSPECTOR but does not run with NODE_USE_V8_PLATFORM so this prevented some Inspector code from running properly on our end; specifically, we were seeing a crash in test/parallel/test-inspector-connect-main-thread.js:

/Users/codebytere/Developer/electron-gn/src/out/Testing/Electron.app/Contents/MacOS/Electron[77672]: ../../third_party/electron_node/src/inspector_agent.cc:834:std::unique_ptr<InspectorSession> node::inspector::Agent::ConnectToMainThread(std::unique_ptr<InspectorSessionDelegate>, bool): Assertion `(parent_handle_) != nullptr' failed.
 1: 0x122cb7c35 node::Abort() [/Users/codebytere/Developer/electron-gn/src/out/Testing/Electron.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 2: 0x122cb79bf node::Assert(node::AssertionInfo const&) [/Users/codebytere/Developer/electron-gn/src/out/Testing/Electron.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 3: 0x122d72a3d node::inspector::Agent::ConnectToMainThread(std::__1::unique_ptr<node::inspector::InspectorSessionDelegate, std::__1::default_delete<node::inspector::InspectorSessionDelegate> >, bool) [/Users/codebytere/Developer/electron-gn/src/out/Testing/Electron.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 4: 0x122d7baeb node::inspector::(anonymous namespace)::JSBindingsConnection<node::inspector::(anonymous namespace)::MainThreadConnection>::New(v8::FunctionCallbackInfo<v8::Value> const&) [/Users/codebytere/Developer/electron-gn/src/out/Testing/Electron.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 5: 0x11a93c05f v8::internal::FunctionCallbackArguments::Call(v8::internal::CallHandlerInfo) [/Users/codebytere/Developer/electron-gn/src/out/Testing/Electron.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 6: 0x11a8d19ee v8::internal::MaybeHandle<v8::internal::Object> v8::internal::(anonymous namespace)::HandleApiCallHelper<true>(v8::internal::Isolate*, v8::internal::Handle<v8::internal::HeapObject>, v8::internal::Handle<v8::internal::HeapObject>, v8::internal::Handle<v8::internal::FunctionTemplateInfo>, v8::internal::Handle<v8::internal::Object>, v8::internal::BuiltinArguments) [/Users/codebytere/Developer/electron-gn/src/out/Testing/Electron.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 7: 0x11a8d0882 v8::internal::Builtin_Impl_HandleApiCall(v8::internal::BuiltinArguments, v8::internal::Isolate*) [/Users/codebytere/Developer/electron-gn/src/out/Testing/Electron.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 8: 0x11a8d037c v8::internal::Builtin_HandleApiCall(int, unsigned long*, v8::internal::Isolate*) [/Users/codebytere/Developer/electron-gn/src/out/Testing/Electron.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
 9: 0x11b838da0 Builtins_CEntry_Return1_DontSaveFPRegs_ArgvOnStack_BuiltinExit [/Users/codebytere/Developer/electron-gn/src/out/Testing/Electron.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
10: 0x11b603557 Builtins_JSBuiltinsConstructStub [/Users/codebytere/Developer/electron-gn/src/out/Testing/Electron.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework]
/Users/codebytere/build-tools/nix/commands/node.sh: line 8: 77672 Abort trap: 6           ELECTRON_RUN_AS_NODE=1 "$ELECTRON_EXEC" "$@"

cc @joyeecheung (who touched some of this recently) and @addaleax

Checklist

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

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/26103/

[joyeecheung]

LGTM, though I wonder who uses NODE_USE_V8_PLATFORM if Electron does not use it?

[addaleax]

@joyeecheung If I understood @codebytere correctly, this is because they have to use the same platform instance for the Chromium parts as well; I think for most other embedders using NODE_USE_V8_PLATFORM would make sense.

[addaleax]

Landed in 71b342f, thanks for the PR!