Emulation - percentHeight behaves differently

In Flex, setting height of 100% on object A does not necessarily mean it stretches to the size of its container B, whereas in Royale this is always the case.

In this example

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The Flex example will show all canvases (red, green, and blue) stretching to a height of 1800 pixels, but in Royale, only the green canvas is sized to 1800 pixels, whereas the rest remain the size of the screen.