Speculative fix for memory issues related to retrying image decompression

[gaaclarke]

b/371512414

This issue had no reproduction but the stacktrace was provided. The theory of this fix is that the ImageResult type is capturing something that doesn't handle being copied and deallocated twice so instead of copying it, we std::move it into a shared_ptr so that it will only be deallocated once.

Also, I just avoid using a std::move when overflowing. The idea here is maybe sometimes deleting the std::move'd item isn't kosher. We know from the stacktrace that it has something to do with overflowing because that would be the only case where something is being deleted.

I've added 2 integration tests that exercises the code where the crash appears to be happening. This is good coverage to have but neither of them reproduced the issue, even with MallocScribble enabled. That's the best we can do without a reproduction.

Thread 7  (id: 0x0000a103)crashed
0x000000010a48ae8c(Flutter -function.h)std::_fl::allocator<impeller::ContextMTL::PendingTasks>::destroy[abi:v15000](impeller::ContextMTL::PendingTasks*)
0x000000010a48b9fc(Flutter -allocator_traits.h:309)impeller::ContextMTL::StoreTaskForGPU(std::_fl::function<void ()> const&, std::_fl::function<void ()> const&)
0x000000010a48b9fc(Flutter -allocator_traits.h:309)impeller::ContextMTL::StoreTaskForGPU(std::_fl::function<void ()> const&, std::_fl::function<void ()> const&)
0x000000010a4d49e4(Flutter -image_decoder_impeller.cc:422)std::_fl::__function::__func<flutter::ImageDecoderImpeller::UploadTextureToPrivate(std::_fl::function<void (sk_sp<flutter::DlImage>, std::_fl::basic_string<char, std::_fl::char_traits<char>, std::_fl::allocator<char>>)>, std::_fl::shared_ptr<impeller::Context> const&, std::_fl::shared_ptr<impeller::DeviceBuffer> const&, SkImageInfo const&, std::_fl::shared_ptr<SkBitmap> const&, std::_fl::optional<SkImageInfo> const&, std::_fl::shared_ptr<fml::SyncSwitch> const&)::$_1, std::_fl::allocator<flutter::ImageDecoderImpeller::UploadTextureToPrivate(std::_fl::function<void (sk_sp<flutter::DlImage>, std::_fl::basic_string<char, std::_fl::char_traits<char>, std::_fl::allocator<char>>)>, std::_fl::shared_ptr<impeller::Context> const&, std::_fl::shared_ptr<impeller::DeviceBuffer> const&, SkImageInfo const&, std::_fl::shared_ptr<SkBitmap> const&, std::_fl::optional<SkImageInfo> const&, std::_fl::shared_ptr<fml::SyncSwitch> const&)::$_1>, void ()>::operator()()
0x000000010a06c234(Flutter -function.h:512)fml::SyncSwitch::Execute(fml::SyncSwitch::Handlers const&) const
0x000000010a4d42f8(Flutter -image_decoder_impeller.cc:408)flutter::ImageDecoderImpeller::UploadTextureToPrivate(std::_fl::function<void (sk_sp<flutter::DlImage>, std::_fl::basic_string<char, std::_fl::char_traits<char>, std::_fl::allocator<char>>)>, std::_fl::shared_ptr<impeller::Context> const&, std::_fl::shared_ptr<impeller::DeviceBuffer> const&, SkImageInfo const&, std::_fl::shared_ptr<SkBitmap> const&, std::_fl::optional<SkImageInfo> const&, std::_fl::shared_ptr<fml::SyncSwitch> const&)
0x000000010a4d3838(Flutter -image_decoder_impeller.cc:538)std::_fl::__function::__func<flutter::ImageDecoderImpeller::Decode(fml::RefPtr<flutter::ImageDescriptor>, unsigned int, unsigned int, std::_fl::function<void (sk_sp<flutter::DlImage>, std::_fl::basic_string<char, std::_fl::char_traits<char>, std::_fl::allocator<char>>)> const&)::$_1, std::_fl::allocator<flutter::ImageDecoderImpeller::Decode(fml::RefPtr<flutter::ImageDescriptor>, unsigned int, unsigned int, std::_fl::function<void (sk_sp<flutter::DlImage>, std::_fl::basic_string<char, std::_fl::char_traits<char>, std::_fl::allocator<char>>)> const&)::$_1>, void ()>::operator()()
0x000000010a06dd1c(Flutter -function.h:512)fml::ConcurrentMessageLoopDarwin::ExecuteTask(std::_fl::function<void ()> const&)
0x000000010a06737c(Flutter -concurrent_message_loop.cc:101)void* std::_fl::__thread_proxy[abi:v15000]<std::_fl::tuple<std::_fl::unique_ptr<std::_fl::__thread_struct, std::_fl::default_delete<std::_fl::__thread_struct>>, fml::ConcurrentMessageLoop::ConcurrentMessageLoop(unsigned long)::$_0>>(void*)
0x000000021d4ff378(libsystem_pthread.dylib + 0x00006378)_pthread_start

Pre-launch Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I read and followed the Flutter Style Guide and the C++, Objective-C, Java style guides.
• I listed at least one issue that this PR fixes in the description above.
• I added new tests to check the change I am making or feature I am adding, or the PR is test-exempt. See testing the engine for instructions on writing and running engine tests.
• I updated/added relevant documentation (doc comments with ///).
• I signed the CLA.
• All existing and new tests are passing.

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[flutter-dashboard]

It looks like this pull request may not have tests. Please make sure to add tests before merging. If you need an exemption, contact "@test-exemption-reviewer" in the #hackers channel in Discord (don't just cc them here, they won't see it!).

If you are not sure if you need tests, consider this rule of thumb: the purpose of a test is to make sure someone doesn't accidentally revert the fix. Ask yourself, is there anything in your PR that you feel it is important we not accidentally revert back to how it was before your fix?

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[flutter-dashboard]

This pull request has been changed to a draft. The currently pending flutter-gold status will not be able to resolve until a new commit is pushed or the change is marked ready for review again.

[jonahwilliams]

LGTM