Fix crash for uncaught exception in MetadataLoader

MetadataLoader just handle FileNotFoundException.
Add more catch for DocumentsContract will rethrow RuntimeException
if provider didn't support getDocumentMetadata.

Bug: 80454526
Test: atest DocumentsUITests:DocumentLoaderTest
Change-Id: I9c1eb23238d77d8dd8be6adf6a8dec10a3d6f564