PVS-Studio warning V610 for Skia

void shadeSpan16_radial_clamp(....) {
  ....
  fy = SkPin32(fy, -0xFFFF >> 1, 0xFFFF >> 1);
  ....
}

This suspicious code was found in Skia project by PVS-Studio static code analyzer.
Warning message is:
V610 Unspecified behavior. Check the shift operator '>>. The left operand '-0xFFFF' is negative. skradialgradient.cpp 82

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