[Editor] Scale handle disappears in Game view after increasing the scale factor from display settings of the monitor.

Steps to Reproduce:
1. Create a new Project.
2. Ensure in the Game View, Scale is set to '1'.
3. Go to Display Settings
4. Increase the Scale value from the display setting of the monitor. (Ex. if the default is set to 100% then update it to 175% or 225%).

Actual Result:
Scale handle disappears in Game view after increasing the scale factor from the display settings of the monitor.

Expected Result:
Scale handle should be visible and working even when the scale value changes.

Environment:
Windows and Mac

Occurring with :
2018.3.0a11, 2018.3.0a1

Working fine with :
2018.2.0f2