Reduce flush timeout to 4s on Android to avoid ANRs

[markushi]

📜 Description

Reduce flush timeout to 4s on Android to avoid ANRs

💡 Motivation and Context

Fixes #2732

💚 How did you test it?

📝 Checklist

• I reviewed the submitted code.
• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• I updated the docs if needed.
• Review from the native team if needed.
• No breaking change or entry added to the changelog.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

🔮 Next steps

[github-actions]

	Messages
📖	Do not forget to update Sentry-docs with your feature once the pull request gets approved.

Generated by 🚫 dangerJS against 69547e4

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	269.20 ms	309.24 ms	40.04 ms
Size	1.72 MiB	2.29 MiB	575.29 KiB

Previous results on branch: feat/flush-timeout-android

Startup times

Revision	Plain	With Sentry	Diff
9349bdf	286.84 ms	366.60 ms	79.76 ms

App size

Revision	Plain	With Sentry	Diff
9349bdf	1.72 MiB	2.29 MiB	575.31 KiB

[codecov]

Codecov Report

Patch coverage: 100.00% and project coverage change: +0.04 🎉

Comparison is base (9020d1b) 81.26% compared to head (69547e4) 81.31%.

Additional details and impacted files

@@               Coverage Diff                @@
##             feat/7.0.0    #2858      +/-   ##
================================================
+ Coverage         81.26%   81.31%   +0.04%     
- Complexity         4560     4564       +4     
================================================
  Files               350      351       +1     
  Lines             16866    16867       +1     
  Branches           2272     2272              
================================================
+ Hits              13706    13715       +9     
+ Misses             2219     2211       -8     
  Partials            941      941              

Impacted Files	Coverage Δ
sentry/src/main/java/io/sentry/Hub.java	75.17% <ø> (ø)
sentry/src/main/java/io/sentry/SentryOptions.java	80.70% <ø> (+0.74%)	⬆️
sentry/src/main/java/io/sentry/SentryTracer.java	94.98% <100.00%> (+0.01%)	⬆️
...y/src/main/java/io/sentry/cache/EnvelopeCache.java	65.36% <100.00%> (ø)
...ry/src/main/java/io/sentry/util/LazyEvaluator.java	100.00% <100.00%> (ø)

... and 1 file with indirect coverage changes

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[romtsn]

@markushi there's one place where I'd like to keep the default 15s for flush timeout and it's this

sentry-java/sentry/src/main/java/io/sentry/cache/EnvelopeCache.java

Lines 430 to 438 in f60279b

	public boolean waitPreviousSessionFlush() {
	try {
	return previousSessionLatch.await(options.getFlushTimeoutMillis(), TimeUnit.MILLISECONDS);
	} catch (InterruptedException e) {
	Thread.currentThread().interrupt();
	options.getLogger().log(DEBUG, "Timed out waiting for previous session to flush.");
	}
	return false;
	}

when we're waiting for the previous unfinished session to be flushed to disk. Would it be possible to keep the 15s value there (we could just have a constant actually)?

[markushi]

@romtsn if you've better reasoning here, please adapt the comment 😊

[romtsn]

yeah, it's good!