Fix error for selecting dom during bookmark upload

[sushant-hiray]

Fixes TypeError while performing bookmark upload:

Following is the console log:

(index):10152 Uncaught TypeError: Cannot read property 'select' of undefined
    at HTMLElement.b._uploadFile ((index):10152)
    at HTMLElement.d ((index):4668)
    at HTMLElement.fire ((index):4690)
    at Object.fire ((index):4678)
    at Object.forward ((index):4685)
    at Object.click ((index):4684)
    at HTMLElement.handleNative ((index):4674)

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[sushant-hiray]

I signed it!

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