Fix sound reorder crash

We were emitting drops when getMouseOverIndex was null, which could happen either when the drop is outside the container, or there were zero boxes to check for ordering. Treat these two cases separately, and continue to not emit drops when outside the container.

This reverts commit 97f8eb63, reversing
changes made to 2e017f06.

Fix backpack squishing

Update scratch-l10n to the latest version 

update scratch-blocks for languages.

Fix delete button on sprite tiles

The previous change that made the images laid out using absolute meant that the close button was layered below the sprite image, making it now clickable

Revert "Adds BorderedMenuItem and use it for delete menu"

Update scratch-blocks

Update scratch-l10n to the latest version 

Update scratch-render to the latest version 

chore(package): update scratch-vm to version 0.2.0-prerelease.2019011…

Closes #4363

Improve layout/paint performance in editor while running a project

Fix issue where you couldn't add sprites from backpack when there are no sprites 

Adds BorderedMenuItem and use it for delete menu

Clear trim handles if trim cannot be completed.

Update scratch-l10n to the latest version 

On some projects, the sprite image changes frequently, which can cause global layouts and paints if we arent careful. Use the same absolute positioning strategy from the sprite library animations to contain layouts to the sprite image itself

Update scratch-vm to the latest version 

There was a useability issue discovered in testing where trying to trim a sound to be of zero length would fail, but just leave the trimmers active. Clear them out, since the trim is invalid

Remove vernier kludge

This reverts commit 68af0af2, reversing
changes made to 3fe75020.

This reverts commit 512915b7.