Fix Travis builds
Supersedes https://github.com/nodejs/node/pull/26992 and incorporates https://github.com/nodejs/node/pull/26968.
First commit:
build: add a `Prepare ccache` job in Travis
Combined compile and test of Node.js where lots of files need to be
compiled (e.g. after a V8 update) is exceeding the time limit for
Travis jobs (50 minutes).
Add a job to Travis that compiles Node.js but doesnt run any tests to
populate the ccache. Introduce staging and move the `Test Suite` job
into a later stage so that it can use the populated ccache.
Second commit:
build: fix skipping of flaky tests on Travis
`PARALLEL_ARGS` is overwritten in the Makefile if `JOBS` is set. Use
`CI_JS_SUITES` instead.
Checklist
-
make -j4 test
(UNIX), orvcbuild test
(Windows) passes -
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