Fixes BUILD.gn if is_fuchsia (legacy embedder) and is_debug

[richkadel]

Current recommended build methods may not trigger this issue, but
while trying different options, building flutter for the first time, I
noticed a build error because defines was assigned twice.

If building with both options is ever supported, I think this
fixes the error.

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List which issues are fixed by this PR. You must list at least one issue.

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[richkadel]

@arbreng - This is a small, probably unimportant change, but a good one for me to familiarize myself with the flutter github workflow.

Are test failures like this (in the Linux Android AOT Engine) common?

File '/b/s/w/ir/cache/builder/src/flutter/testing/scenario_app/android/app/build/outputs/apk/debug/app-debug.apk' not found.

What's the best practice for resolving?

Referencing an issue:

What's the best practice if there is no existing issue, for a (trivial?) change like this? I see https://github.com/flutter/flutter/wiki/Issue-hygiene#file-bugs-for-everything . Is that practice used religiously or best judgement?

Adding a test:

I don't think this is testable since unopt is currently not possible (AFAICT)

[arbreng]

Are test failures like this (in the Linux Android AOT Engine) common?

Did you rebase your change onto master before pushing it? this may be a consequence of your change being based on an old commit.

[richkadel]

Thanks. You're probably right, I will double check that.

…

On Fri, Apr 30, 2021, 4:06 PM David Worsham ***@***.***> wrote: Are test failures like this (in the Linux Android AOT Engine) common? Did you rebase your change onto master before pushing it? this may be a consequence of your change being based on an old commit. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#25858 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AA5GMYSAWNWSO5D4A3OHFO3TLMZWVANCNFSM434ZBTFQ> .

[chinmaygarde]

Presubmit failures are currently blocked on a P0. Adding the CQ label.

[fluttergithubbot]

This pull request is not suitable for automatic merging in its current state.

• The status or check suite Windows Android AOT Engine has failed. Please fix the issues identified (or deflake) before re-applying this label.
• The status or check suite Windows Host Engine has failed. Please fix the issues identified (or deflake) before re-applying this label.
• The status or check suite Windows UWP Engine has failed. Please fix the issues identified (or deflake) before re-applying this label.