[4.0.0-rc.5] Blend mode applied to masked sibling

[leemanhopeter]

Version

• Phaser Version: 4.0.0-rc.5

Description

If a game object inside a container has a blend mode, it will also become the blend mode of the sibling

Example Test Code

https://phaser.io/sandbox/6o5q1YA7

You can see that the green rectangle also has ADD blend mode which should only be applied to the red rectangle.

Note that if the red rectangle is added last, then this error will not occur.

Note also that if subContainer is not masked, or if the mask is not on subContainer but on the green rectangle, then this error will also not occur.