Fixes ChatInput obscure issue

[rohitbhoite]

Fixes ChatInput obscure issue.

After:

Before:

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[rohitbhoite]

Can we merge this?

[csells]

@rohitbhoite I'm doing some work on the AI Toolkit next week. Can you log the bug with the details of what you're seeing (I see images above, but no explanation) and on what platform you're seeing this so I can repro it and test your fix?

[rohitbhoite]

@csells This issue occurs on a real Google Pixel 8 device. When the user opens the app, the Chat Input Box is hidden behind the bottom System Bar.

[csells]

This is the kinda thing you'd wanna chat about in an issue, if you'd be willing to create one.

Can you reproduce it on the emulator in case I don't have access to a Google Pixel 8?

[rohitbhoite]

Yes as I mentioned above I have observed this issue on Google pixel 8. The proposed change in this pr will fix this issue.

[csells]

closing this PR, as I cannot accept it without the CLA signature. however, I was able to reproduce and fix the issue by enabling Android's 3-button nav. The fix is in this PR under review.