Fix: Fixed thumbails not loading in MTP devices

[gave92]

Resolved / Related Issues

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• Closes Bug: Thumbnails don't load for MTP devices (Phones) #15084

Added back some code removed in #14423 which is necessary for loading thumbails in MTP.

Steps used to test these changes

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1. Verify that icons are loaded in MTP devices
2. Verify that loading on normal drives is not impacted

[yaira2]

I was thinking we could take this a step forward with a single method in FileThumbnailHelper that would first attempt using the Win32 method, and StorageItem as a fallback.

[gave92]

Ok now thumbnails work in file list, in properties window and preview pane 💪

[yaira2]

I'm concerned about maintaining two separate thumbnail systems (we did in the past, with much trouble).
Is there anything we can do with Win32Helper.GetIcon and avoid the need to use StorageThumbnail?

[yaira2]

I'm concerned about maintaining two separate thumbnail systems (we did in the past, with much trouble). Is there anything we can do with Win32Helper.GetIcon and avoid the need to use StorageThumbnail?

@gave92 this is potentially solvable when we switch ShellViewModel to the new storage abstractions.