Add diagnostic for typeof x === undefined #6270

Job	Run time
macOS x86_64	8m 31s
macOS AArch64	1s
Linux x86_64	3m 15s
Linux ARM	1m 42s
Linux AArch64	1m 47s
Windows x86	7m 7s
Windows x64	6m 11s
Windows ARM	1m 40s
Windows ARM64	1m 40s
Chocolatey package	0s
test on ${{ matrix.os.name }}	0s
Scoop package	0s
MSIX installer	0s
test Chocolatey package	0s
npm package	0s
winget manifests	0s
test npm package on ${{ matrix.os.name }} with ${{ matrix.manager.name }}	0s
	31m 54s

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