[PartitionAlloc] Disable periodic purge for non-DCHECK() builds.

The issues seen on Windows (see crbug.com/1155905) also happen on
Android, so disable it everywhere. Keep it for DCHECK() builds to
investigate the root cause, which hasn't been identified.

Bug: 1155905, 998048
Change-Id: I4d8bf3c6af3e745b5956a0a12413899c2e1c4056
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2612966Reviewed-by: Arthur Sonzogni <arthursonzogni@chromium.org>
Commit-Queue: Benoit L <lizeb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#840586}

content/app/content_main_runner_impl.cc

@@ -1011,11 +1011,10 @@ int ContentMainRunnerImpl::RunBrowser(MainFunctionParams& main_params,
   // Enable PCScan once we are certain that FeatureList was initialized.
   EnablePCScanForMallocPartitionsIfNeeded();
 
-  // This is only relevant for PartitionAlloc-Everywhere builds.
-  // Temporarily disabled for non-DCHECK() builds on Windows, due to possibly
-  // related crashes (crbug.com/1155905).
-#if BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC) && \
-    !(defined(OS_WIN) && !DCHECK_IS_ON())
+  // This is only relevant for PartitionAlloc-Everywhere builds. Temporarily
+  // disabled for non-DCHECK() builds, due to possibly related crashes
+  // (crbug.com/1155905).
+#if BUILDFLAG(USE_PARTITION_ALLOC_AS_MALLOC) && DCHECK_IS_ON()
   base::internal::ThreadCacheRegistry::Instance().StartPeriodicPurge();
 #endif