#1978 Shifting signed 32-bit value by 31 bits is undefined behaviour

[Zufu Liu]

CppCheck 1.81 warnings:
Shifting signed 32-bit value by 31 bits is undefined behaviour.

for ViewStyle.cxx line 195:

const int maskBit = 1 << markBit;

a quick fix would be:

const int maskBit = 1U << markBit;

[Neil Hodgson]

Committed as [2db052].