RNTester: Crash loading <Image> page

[kmelmon]

The page in RNTester is having issues and crashes when you try to load it.

Callstack to the crash:

React.UWP.dll!winrt::to_hresult() Line 4298	C++
React.UWP.dll!winrt::terminate() Line 4372	C++
React.UWP.dll!std::experimental::coroutine_traits<winrt::fire_and_forget,react::uwp::ReactImage *,react::uwp::ImageSource>::promise_type::unhandled_exception() Line 7942	C++

React.UWP.dll!react::uwp::ReactImage::Source$_ResumeCoro$2() Line 112 C++
React.UWP.dll!react::uwp::ReactImage::Source$_InitCoro$1() Line 112 C++
React.UWP.dll!react::uwp::ReactImage::Source(react::uwp::ImageSource source) Line 112 C++
React.UWP.dll!react::uwp::ImageViewManager::setSource(winrt::Windows::UI::Xaml::Controls::Canvas canvas, const folly::dynamic & data) Line 162 C++
React.UWP.dll!react::uwp::ImageViewManager::UpdateProperties(react::uwp::ShadowNodeBase * nodeToUpdate, const folly::dynamic & reactDiffMap) Line 124 C++
React.UWP.dll!react::uwp::ShadowNodeBase::updateProperties(const folly::dynamic && props) Line 28 C++
React.UWP.dll!facebook::react::UIManager::createView(__int64 tag, std::string && className, __int64 __formal, folly::dynamic && props) Line 260 C++
React.UWP.dll!facebook::react::UIManagerModule::getMethods::__l2::(folly::dynamic args) Line 451 C++

Debug spew says:
Exception thrown at 0x764A35D2 (KernelBase.dll) in Playground.exe: WinRT originate error - 0x80070057 : 'legacy_image is not a valid absolute URI.'.
Exception thrown at 0x764A35D2 in Playground.exe: Microsoft C++ exception: winrt::hresult_invalid_argument at memory location 0x04AFC88C.

Exception thrown at 0x764A35D2 in Playground.exe: Microsoft C++ exception: [rethrow] at memory location 0x00000000.

Debugging back to the property setter, we have this:

	Name	Value	Type
◢	sources[0]	{uri="legacy_image" method="" bundleRootPath="ms-appx:///Bundle/" ...}	react::uwp::ImageSource
	▶ uri	"legacy_image"	std::string
	▶ method	""	std::string
	▶ bundleRootPath	"ms-appx:///Bundle/"	std::string

So, we have an with a uri of "legacy_image" and that's failing to resolve to a valid resource in our appx package. It looks like we either aren't packaging image resources for RNTester properly, or aren't resolving the URI propertly.

[kmelmon]

This may be a dupe of #2452

[kmelmon]

Marlene thinks the image won't load because the test was just copied from Android and the image is only part of the Android bundle.

[jonthysell]

This test assumes that the host app has some kind of native image/resource and that legacy_image is a valid identifier.

For our code, we automatically resolve the whole uri to ms-appx://Bundle/legacy_image. If RNTester had its own proper host app, we could do either of the following:

1. Include an image file named legacy_image in the Bundle folder, so that it gets resolved. OR
2. Include an image resource with the identifier legacy_image and update our lookup code to look for that resource (can UWP apps even do that, or do we still need an ms-appx:// uri?)

However, we don't have a proper RNTester app, we have Playground. So we could do either of the above to the Playground app, but it would a weird dependency for Playground.

We should, however, not ever crash because of missing images. Is there a standard image not found image we could use?

[jonthysell]

Ok, it looks like it's expected to be an unsafe operation, and there are different rules for iOS and Android: https://reactnative.dev/docs/images#images-from-hybrid-apps-resources

We should update the logic in ImageViewManager::setSource() to properly handle all of the supported image uri types:

• Regular URI (just load)
• Filesystem URI (just load)
• Bundled asset URI (append bundle root)
• Explicit package URI

I think that's all of them, but we should test the different configs (debug, release, with/without bundles, with/without assets)

[jonthysell]

For this particular bug, I think the right thing to do is not support a plain legacy_image identifier. We should just not load an image.

Potentially though we could add an example where we explicitly set an ms-appx:// uri and it should work.

[jonthysell]

PR out to prevent crashing when trying to load invalid uris, just fail.