message: SSAO: fix high-quality upsampling
  Another mediump issue.
diff: @@ -58,9 +58,9 @@ float evaluateSSAO() {
  depths.z = unpack(vec2(dg.z, db.z));
  depths.w = unpack(vec2(dg.w, db.w));
  depths *= -frameUniforms.cameraFar;
  - mat4 m = getViewFromWorldMatrix();
  - float d = dot(vec3(m[0].z, m[1].z, m[2].z), shading_position) + m[3].z;
  - vec4 w = (vec4(d) - depths) * frameUniforms.aoSamplingQualityAndEdgeDistance;
  + highp mat4 m = getViewFromWorldMatrix();
  + highp float d = dot(vec3(m[0].z, m[1].z, m[2].z), shading_position) + m[3].z;
  + highp vec4 w = (vec4(d) - depths) * frameUniforms.aoSamplingQualityAndEdgeDistance;
  w = max(vec4(MEDIUMP_FLT_MIN), 1.0 - w * w) * b;
  return dot(ao, w) * (1.0 / (w.x + w.y + w.z + w.w));
  } else {
  