Fixed ScrollView's .scrollToEnd to refrain from exceeding start boundary.

[Guardiannw]

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Explain the motivation for making this change. What existing problem does the pull request solve?

The problem occurs when a ScrollView's content height is smaller than the ScrollView height. If the method scrollToEnd is called on the ScrollView, it will pull the content down until the bottom of the content is aligned with the bottom of the Scrollview container.

This fix will ensure the proper functionality: That the furthest the ScrollView can scroll down is to where the top of the content container is at the origin (i.e., the ScrollView scroll number cannot be less than 0).

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I tested on a scenario where the ScrollView is almost the full size of the screen, and the content of the ScrollView has a height of much less. In this situation, the scrollToEnd method was executed and the content stayed in the same position. This is the intended behavior. If the content of the ScrollView is smaller than the height of the ScrollView, then the scrollToEnd method should not scroll anywhere.

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[Guardiannw]

The checks did not pass, but I don't think it is due to the code I changed. I didn't change any android code, but it was android scripts that failed.

[sbaar]

Confirmed. This code fixed an issue that would cause scrollToEnd() to scroll past the end. The pr keeps the items vertically aligned at the top, as expected

[gabriel]

I've encountered this bug as well.

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